International journal for parasitology最新文献

{"title":"Dirofilaria spp. infection in cats from the Mediterranean basin: diagnosis and epidemiology","authors":"Mariaelisa Carbonara ,&nbsp;Livia Perles ,&nbsp;Luigi Venco ,&nbsp;Simona Gabrielli ,&nbsp;Vanessa R. Barrs ,&nbsp;Guadalupe Miró ,&nbsp;Elias Papadopoulos ,&nbsp;Clara Lima ,&nbsp;Emilie Bouhsira ,&nbsp;Gad Baneth ,&nbsp;Nikola Pantchev ,&nbsp;Roberta Iatta ,&nbsp;Jairo Alfonso Mendoza-Roldan ,&nbsp;Nicola Decaro ,&nbsp;Bettina Schunack ,&nbsp;Giovanni Benelli ,&nbsp;Domenico Otranto","doi":"10.1016/j.ijpara.2025.01.011","DOIUrl":"10.1016/j.ijpara.2025.01.011","url":null,"abstract":"<div><div><em>Dirofilaria immitis</em> and <em>Dirofilaria repens</em>, causing heartworm disease and subcutaneous dirofilariosis, respectively, are zoonotic mosquito-borne filarioids infecting a plethora of hosts including cats. Only fragmented data are available on the diagnosis and epidemiology of feline dirofilariosis. We assessed the occurrence of both nematode infections, their risk factors and clinicopathological abnormalities in cats, from six countries of the Mediterranean Basin. In addition, <em>Wolbachia</em> spp. endosymbionts were assessed in <em>Dirofilaria</em> spp.-positive animals. Blood and sera samples were obtained from cats with outdoor access from Spain (<em>n</em> = 354), Portugal (<em>n</em> = 287), Italy (<em>n</em> = 125), Greece (<em>n</em> = 116), Israel (<em>n</em> = 101) and France (<em>n</em> = 100). Cat sera were tested by both direct antigenic (SNAP test, commercial ELISA kit) and indirect antibodies (in-house ELISA) serological tools, and blood samples by real time and conventional PCR targeting <em>Dirofilaria</em> spp. DNA, followed by sequencing. A statistical analysis was run to assess the link between <em>Dirofilaria</em> spp. infection and independent variables, as well as among feline immunodeficiency virus (FIV) and/or feline leukaemia virus (FeLV) co-infections, and clinicopathological abnormalities. Overall, 3.8% (i.e., 41/1,083) cats scored positive for <em>Dirofilaria</em> spp. infection with prevalences ranging from 2% in Israel to 7.8% in Greece. Of the 41 positive cats, 16 were infected by <em>D. immitis</em> (by SNAP test and/or PCR) and two by <em>D. repens</em> (by PCR); the remaining animals were antibody-positive for <em>Dirofilaria</em> spp. using the in-house ELISA. <em>Wolbachia</em> DNA was detected in one <em>D. immitis</em>-infected cat. Nematode positivity was significantly associated with age, breed, hyporexia, dandruff, and dyspnoea. This study provides data on the prevalence of <em>Dirofilaria</em> spp. infection in cats from the Mediterranean Basin, as well as new insights on its diagnosis, revealing the importance of performing strategic chemoprophylactic treatments for cats living in areas where the infection is endemic in dogs.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 6","pages":"Pages 317-325"},"PeriodicalIF":3.7,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143255634","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":"Bat microfilariae in the cityscape: a transmission tale between bats, mites, and bat flies","authors":"Román Espinal-Palomino ,&nbsp;Ana Celia Montes de Oca-Aguilar ,&nbsp;Martha Pilar Ibarra-López ,&nbsp;Víctor M. Vidal-Martínez ,&nbsp;Carlos N. Ibarra-Cerdeña","doi":"10.1016/j.ijpara.2024.11.001","DOIUrl":"10.1016/j.ijpara.2024.11.001","url":null,"abstract":"<div><div><em>Litomosoides</em> includes filarial nematodes capable of infecting various vertebrate species. While <em>Litomosoides</em> has been extensively studied in rodents, research on its association with bats remains limited. The transmission dynamics of this parasite are complex, involving moving between different invertebrate hosts before reaching the final host. Most investigations concerning microfilariae have concentrated on their morphological characteristics, with scant attention paid to ecological aspects, particularly in human-altered landscapes. This study represents the first known documentation of <em>Litomosoides</em> in bats within an urban environment. It investigates their response to urbanization in their interaction with the synanthropic bat <em>Artibeus jamaicensis</em> and its ectoparasites. The objective was to explore the influence of urban landscapes on <em>Litomosoides</em> prevalence in synanthropic hosts. Blood samples were collected along urban–rural gradients, and parasite presence was confirmed through direct observation in blood smears and PCR. Phylogenetic analysis based on the mitochondrial cytochrome <em>c</em> oxidase subunit 1 gene (COX1), which exhibited robust support values, indicates that the microfilaria found in <em>A. jamaicensis</em> is closely related to <em>Litomosoides chandleri</em>. However, it also suggests the possibility of an unidentified, and therefore potentially new, species within the genus <em>Litomosoides</em>. Additionally, <em>Litomosoides</em> DNA was detected in <em>Periglischrus iheringi</em> (Acari: Spinturnicidae) and in the bat fly <em>Trichobius intermedius</em> collected from the bat. The parasite sequences obtained from these three interacting species exhibited a genetic distance as low as 0.002. The highest prevalences were recorded in forested areas (28.6%) compared with urban areas (21.2%). However, within the urban landscape, prevalence varied from 3.8% to 21.2%, being highest in densely built-up areas. Analysis of the urban landscape suggested that the prevalence of <em>Litomosoides</em> in <em>A. jamaicensis</em> is the result of a multifactorial and synergistic process involving ectoparasite load, host abundance, and the extent of impervious surfaces (NDBI).</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 2","pages":"Pages 79-94"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142619799","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":"Dense aquatic vegetation can reduce parasite transmission to amphibians","authors":"Marin Milotic ,&nbsp;Dino Milotic ,&nbsp;Janet Koprivnikar","doi":"10.1016/j.ijpara.2024.11.003","DOIUrl":"10.1016/j.ijpara.2024.11.003","url":null,"abstract":"<div><div>Submerged aquatic vegetation (macrophytes) can provide prey with refuges from predators and may perform a similar role for interactions with other natural enemies such as parasites. This could occur by interfering with the ability of free-swimming infectious parasite stages to locate or move towards hosts, reducing infections. Alternatively, infections may increase if macrophytes reduce host anti-parasite behaviours such as detection or evasion. Both scenarios could be affected by macrophyte density and structural complexity. Here we investigated whether experimental infection of tadpoles (<em>Rana sylvatica</em> and <em>Rana pipiens</em>) by parasitic flatworms (the trematodes <em>Ribeiroia ondatrae</em> and <em>Echinostoma</em> spp. was affected by the presence of artificial vegetation with varying density and complexity (simple versus branching), as well as tadpole activity under these conditions. Macrophyte presence significantly reduced tadpole infection loads only in the highest density treatment, but there was no effect of structural complexity. Related to this, tadpoles spent significantly more time near aquatic vegetation when it was dense but showed no preference for either structural type. Our results indicate that aquatic vegetation can reduce parasite transmission in certain scenarios, with further studies needed to explore how structural complexity in natural systems can affect host-parasite interactions, considering the massive physical alterations possible through eutrophication and the introduction of invasive plant species.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 2","pages":"Pages 95-102"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142619800","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 parasitic nematode Haemonchus contortus lacks molybdenum cofactor synthesis, leading to sulphite sensitivity and lethality in vitro","authors":"Robert A. Brinzer,&nbsp;Jennifer R. McIntyre,&nbsp;Collette Britton,&nbsp;Roz Laing","doi":"10.1016/j.ijpara.2024.11.004","DOIUrl":"10.1016/j.ijpara.2024.11.004","url":null,"abstract":"<div><div>Sulphite oxidase has an essential role in detoxifying environmental and endogenously generated sulphite into sulphate and requires the molybdenum cofactor (Moco) to function. Until recently it was believed that the synthesis pathway for Moco was so important for survival that it was conserved in all multicellular animals. Here we report the use of comparative genomics to identify the absence of the first enzyme involved in Moco synthesis in <em>Haemonchus contortus</em>, a highly pathogenic and economically important helminth of livestock that, similar to many parasitic nematode species, has proved difficult to maintain in vitro. We show that Moco deficiency in <em>Haemonchus</em> leads to a high sensitivity to environmental sulphite and limits the ability to maintain the early parasitic larval stages in vitro. Analogous losses in Moco synthesis in other recently sequenced nematode species are also identified. These findings may lead to improved culture methods for parasitic nematodes and to novel approaches for their control.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 2","pages":"Pages 117-128"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142768446","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":"Do specialist and generalist parasites differ in their prevalence and intensity of infection? A test of the niche breadth and trade-off hypotheses","authors":"Sonia Cebrián-Camisón ,&nbsp;Josué Martínez-de la Puente ,&nbsp;María José Ruiz-López ,&nbsp;Jordi Figuerola","doi":"10.1016/j.ijpara.2024.11.009","DOIUrl":"10.1016/j.ijpara.2024.11.009","url":null,"abstract":"<div><div>Studying host specificity is crucial to understanding the ability of parasites to spread to new hosts and trigger disease emergence events. The relationship between host specificity and parasite prevalence and infection intensity, has typically been studied in the context of two opposing hypotheses. According to the trade-off hypothesis generalist parasites, which can infect a broad range of hosts, will reach a lower prevalence and infection intensity than more specialist parasites due to the higher costs to adapt to multiple host immune systems. In contrast, the niche breadth hypothesis proposes that generalists’ ability to infect more host species makes them more efficient in colonising host communities and thus they are found at higher prevalences and infection intensities. This study aims to test these hypotheses using the widespread avian malaria parasites of the genera <em>Plasmodium</em> and the related malaria-like parasite <em>Haemoproteus.</em> Overall, 1188 wild house sparrows from 17 localities in southwestern Spain were screened for parasite presence and intensity of infection. For each lineage found infecting house sparrows, we estimated host specificity as i) the number of different bird taxa infected by that lineage according to the MalAvi database and ii) an index that accounts for the phylogenetic relatedness between the host species. Parasite infections were recorded in 419 house sparrows, and eight <em>Plasmodium</em> and three <em>Haemoproteus</em> lineages were identified. Prevalence was positively associated with the number of host species. Lineages found in more localities showed both higher prevalence and host range. Overall, these results support the niche breadth hypothesis in relation to blood parasites infecting house sparrows.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 2","pages":"Pages 129-136"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142785562","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":"Insights into extracellular vesicle biogenesis and secretion of the tapeworm Hymenolepis diminuta: host interaction and cultivation dynamics","authors":"Hynek Mazanec ,&nbsp;Javier Sotillo ,&nbsp;Peter Koník ,&nbsp;Nikol Bušková ,&nbsp;Jiří Kyslík ,&nbsp;Zdenko Gardian ,&nbsp;Tomáš Bílý ,&nbsp;Kateřina Jirků ,&nbsp;Roman Kuchta","doi":"10.1016/j.ijpara.2024.11.005","DOIUrl":"10.1016/j.ijpara.2024.11.005","url":null,"abstract":"<div><div>Extracellular vesicles (EVs) from parasites have been identified as potent modulators of host-parasite interactions. However, their biogenesis and secretory activity are still poorly understood. Here we present a comprehensive examination of the secretory dynamics of two distinct EV fractions isolated from the adult tapeworm <em>Hymenolepis diminuta</em>. Additionally, we perform a detailed analysis of changes in proteomic content and morphology during EV secretion, utilising electron tomography to shed light on a previously described novel mechanism of EV biogenesis via bead-like protrusion. Our findings reveal a significant decrease in EV secretion between 24 and 48 h of <em>in vitro</em> cultivation when external host stimuli are no longer present. Finally, this study addresses, for the first known time, the potential bias in EV analysis resulting from extended <em>in vitro</em> cultivation of model parasites.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 2","pages":"Pages 69-77"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142785568","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":"Mitogenomic analysis of the position of the Azygiidae and constituent genera, with a new species of Azygia","authors":"Danimar López-Hernández ,&nbsp;Florian B. Reyda ,&nbsp;Wenxiang Li ,&nbsp;Hudson A. Pinto ,&nbsp;Sean A. Locke","doi":"10.1016/j.ijpara.2024.11.002","DOIUrl":"10.1016/j.ijpara.2024.11.002","url":null,"abstract":"<div><div>The Azygiidae Looss, 1899 is a family of digeneans with a Holarctic distribution in which members of some genera mature in marine elasmobranchs while others occur only in freshwater teleosts. Some have questioned whether the marine genus <em>Otodistomum</em> Stafford, 1904 indeed belongs to the same family as the freshwater azygiid genera, namely <em>Azygia</em> Looss, 1899, <em>Proterometra</em> Horsfall, 1933, and <em>Leuceruthrus</em> Marshall and Gilbert, 1905. We present phylogenetic analyses based on mitochondrial genomes, rDNA operons, and partial cytochrome <em>c</em> oxidase I (<em>Cox1</em>) sequences from North American and Asian species that support the monophyly of Azygiidae, and placement of Azygioidea in the suborder Hemiurata, in contrast to recently published mitochondrial genome phylogenies. All phylogenies indicate that <em>Azygia</em> includes <em>Leuceruthrus</em>, which we therefore propose to be a junior synonym, together with suppression of the Leuceruthrinae. The status of <em>Proterometra</em> was equivocal, with support in some but not all analyses of 28S, but not in other markers. We describe a new species of <em>Azygia</em> from northeastern North America. Our results confirm the morphological variability of adults in <em>Azygia</em>, with worm size positively correlated with host size in <em>Azygia angusticauda</em>. Phylogenies suggest a marine origin for the Azygiidae, and a Palearctic origin for freshwater azygiids, with a single trans-Atlantic radiation to the Nearctic.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 2","pages":"Pages 103-115"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142619801","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":"In vitro culture of the parasitic stage larvae of hematophagous parasitic nematode Haemonchus contortus","authors":"Lu Liu ,&nbsp;Zongshan Zhang ,&nbsp;Fuqiang Liu ,&nbsp;Hui Liu ,&nbsp;Lisha Ye ,&nbsp;Feng Liu ,&nbsp;Nishith Gupta ,&nbsp;Chunqun Wang ,&nbsp;Min Hu","doi":"10.1016/j.ijpara.2025.01.007","DOIUrl":"10.1016/j.ijpara.2025.01.007","url":null,"abstract":"<div><div>Current research on common parasitic nematodes is limited because their infective stages cannot be propagated in vitro. Here, we report a culture system for developing L4s of <em>Haemonchus contortus</em>, a blood-feeding nematode of ruminants. Our results demonstrated that a proportionate mixture of NCTC-109 to Luria-Bertini (1:2) media promoted the formation of early L4s and then into late L4s upon inclusion of 12.5% (v/v) defibrinated blood, albeit with a decline in survival. Adding antioxidants (0.3 mg/mL of L-glutathione or 200 nmol of vitamin C) improved survival of L4s, with approximately 90% developing to late L4s by 22 days. These L4s showed parallel morphological features (such as digestive and reproduction systems) compared with in vivo L4s at day 7 (following challenge infection), although with delayed development. Our work optimized the in vitro culture system for L4s while providing an important platform for in-depth molecular research on <em>Haemonchus</em> and other related parasitic nematodes.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 5","pages":"Pages 263-271"},"PeriodicalIF":3.7,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7617482/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143028432","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":"Trichinella spiralis extracellular vesicles induce anti-inflammatory and regulatory immune responses in vitro","authors":"Sofija Glamočlija ,&nbsp;Ljiljana Sabljić ,&nbsp;Sergej Tomić ,&nbsp;Jelena Đokić ,&nbsp;Nataša Radulović ,&nbsp;Alisa Gruden-Movsesijan ,&nbsp;Maja Kosanović","doi":"10.1016/j.ijpara.2025.01.008","DOIUrl":"10.1016/j.ijpara.2025.01.008","url":null,"abstract":"<div><div>The helminth <em>Trichinella spiralis</em>, 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 (<em>Ts</em>EVs) the aim of this study was to investigate the impact of <em>Ts</em>EVs, isolated from ES L1 products, on phenotypic and functional characteristics of DCs and to elucidate whether <em>Ts</em>EVs could reproduce the immunomodulatory effects of the complete ES L1 product. Monocyte-derived DCs treated with <em>Ts</em>EVs 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 <em>Ts</em>EV-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. <em>Ts</em>EVs promoted the capacity of DCs to drive polarization of Th2 and anti-inflammatory responses, and impaired their capacity to induce Th1/Th17 polarization. Moreover, <em>Ts</em>EV-treated DCs possessed a high capacity to induce conventional FoxP3 + regulatory T cells, as well as unconventional T regulatory (Tr1) cells. Tolerogenic properties of <em>Ts</em>EV-treated DCs were retained even after challenge with a pro-inflammatory stimulus. These findings highlight the potential of <em>Ts</em>EVs to induce immune tolerance, suggesting their potential use as therapeutics for the treatment of inflammatory disorders.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 6","pages":"Pages 299-315"},"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,&nbsp;Jacobus C. de Roode","doi":"10.1016/j.ijpara.2025.01.006","DOIUrl":"10.1016/j.ijpara.2025.01.006","url":null,"abstract":"<div><div>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 <em>Ophryocystis elektroscirrha</em> exhibits across the metamorphosis of its host, the monarch butterfly. We found evidence that <em>O. elektroscirrha</em> differentiates in concordance with the ecological turnover imposed by monarch transitions to different stages, and that patterns of transcriptional decoupling across <em>O. elektroscirrha</em> 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.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 6","pages":"Pages 273-279"},"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}