Acta tropica最新文献

{"title":"Cross-species virulence strategies of Mycobacterium avium subsp. paratuberculosis: Gene expression and infection progression in sheep and guanacos","authors":"Miguel Salgado ,&nbsp;Carlos Tejeda ,&nbsp;Pamela Steuer ,&nbsp;Claudio A. Moraga ,&nbsp;Sergio Radic-Schilling ,&nbsp;Paulo Corti","doi":"10.1016/j.actatropica.2025.107853","DOIUrl":"10.1016/j.actatropica.2025.107853","url":null,"abstract":"<div><div>Pathogenic bacteria adapt to their hosts modulating virulence-gene expression. This flexible and responsive virulence is frequently associated with the capacity of bacterial pathogens to infect a variety of host species, including wildlife and domestic animals. <em>Mycobacterium avium</em> subsp. <em>paratuberculosis</em> (MAP) is the causative agent of Johne's disease and infects a broad range of ruminant-like herbivores. While its virulence has been well-studied in livestock, its behavior in wildlife hosts remains poorly understood. By studying infection progression and virulence-gene expression, we gain important insights into how bacteria cause infection and how the host reacts. Here, we examine virulence of MAP isolates obtained from fecal samples of domestic sheep and guanaco (<em>Lama guanicoe</em>), including MAP infection progression and expression of six MAP genes, two oxidative stress response genes (<em>katG, sodA</em>) and four virulence-associated genes (<em>impA, umaA1, papA2, kdpC</em>). The progression of the infection was monitored using fecal shedding estimates as a proxy indicator. Compared to guanaco, sheep exhibited both noticeably higher MAP shedding and expression of all six genes. These results indicate that MAP modifies its expression profile in response to the host environment, and also to a possible host-specific transcriptional modulation of MAP. These data did not exclude guanaco as a potential source of infection for both their own species and for other MAP-susceptible species in the area. In mixed species-use landscapes, managing cross-species transmission and MAP persistence requires an understanding of these mechanisms.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"271 ","pages":"Article 107853"},"PeriodicalIF":2.5,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145181862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular evidence of Histomonas meleagridis in Ascaridia galli from chickens in Thailand: Possibility of transmission pathways","authors":"Witchuta Junsiri ,&nbsp;Piyanan Taweethavonsawat","doi":"10.1016/j.actatropica.2025.107850","DOIUrl":"10.1016/j.actatropica.2025.107850","url":null,"abstract":"<div><div>The poultry industry in Thailand plays a vital role in national food security and economic stability. <em>Ascaridia galli</em> is among the most prevalent and pathogenic nematodes affecting chickens, contributing to significant losses in global poultry production. Histomoniasis, another serious disease, causes severe liver and caecal lesions and high morbidity. Despite the importance of both parasites, the information of the molecular characterization of <em>A. galli</em> and the detection of <em>Histomonas meleagridis</em> within adult <em>A. galli</em> in Thailand is still limited. In this study, cytochrome c oxidase subunit 1 (COI) and 12S ribosomal RNA (12S rRNA) genes were amplified by polymerase chain reaction (PCR) from 20 adult <em>Ascaridia</em> nematodes. Additionally, 18S ribosomal RNA (18S rRNA) gene amplification was performed to confirm <em>H. meleagridis</em> infection. The resulting sequences were aligned and compared with reference sequences of <em>A. galli, H. meleagridis</em>, and other related protozoa. Both COI and 12S rRNA sequences confirmed the identity of the nematodes as <em>A. galli</em>. Notably, <em>H. meleagridis</em> DNA was detected exclusively in female <em>A. galli</em> specimens. These findings suggest that female <em>A. galli</em> may act as a potential reservoir host in the transmission cycle of <em>H. meleagridis</em> in chickens. This study represents the molecular evidence of <em>H. meleagridis</em> DNA within <em>A. galli</em> collected from the intestinal contents of deceased chickens clinically suspected of histomoniasis.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"271 ","pages":"Article 107850"},"PeriodicalIF":2.5,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145156211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Immunomodulatory effects of Cryptococcus neoformans capsular polysaccharides on macrophage infected with Trypanosoma cruzi","authors":"Joyce Cristina Guimarães-de-Oliveira ,&nbsp;Elias Barbosa da Silva-Junior ,&nbsp;Mayra Silva Machado Meyrelles ,&nbsp;Letícia R. Vilas Diniz ,&nbsp;Luciana Polaco Covre ,&nbsp;Leonardo Freire-de-Lima ,&nbsp;Israel Diniz-Lima ,&nbsp;Afonso Santine M.M. Velez ,&nbsp;Lucia Mendonça-Previato ,&nbsp;Jose Osvaldo Previato ,&nbsp;Alexandre Morrot ,&nbsp;Herbert Leonel de Matos Guedes ,&nbsp;Debora Decote-Ricardo ,&nbsp;Celio Geraldo Freire-de-Lima","doi":"10.1016/j.actatropica.2025.107849","DOIUrl":"10.1016/j.actatropica.2025.107849","url":null,"abstract":"<div><div><em>Cryptococcus neoformans</em> is an opportunistic fungal pathogen with a global distribution and is the causative agent of cryptococcosis, a disease that primarily affects immunocompromised individuals. The infection typically begins in the lungs and, in severe cases, can progress to meningoencephalitis and even death. Biochemical studies have shown that the fungal capsule is predominantly composed of glucuronoxylomannan (GXM), which accounts for approximately 88% of the total composition, followed by glucuronoxylomannogalactan (GXMGal, ∼10%) and mannoproteins (∼2%). Purified capsular components have been reported to exhibit distinct immunomodulatory effects: while GXM predominantly exerts immunosuppressive activity, inhibiting immune responses, GXMGal has been associated with immunoprotective properties.</div><div>To evaluate these differential immunomodulatory effects in another infection model, we employed an <em>in vitro</em> system using murine macrophages infected with the <em>Trypanosoma cruzi</em> DM28c strain, followed by treatment with either GXM or GXMGal. Our results demonstrated that at 7 and 10 days post-infection, the number of trypomastigotes released was higher in GXM-treated conditions compared to GXMGal-treated conditions, even when macrophages were stimulated with interferon-γ. Additionally, amastigote counts were higher in macrophages treated with GXM, whereas GXMGal-treated conditions showed increased nitric oxide production. Cytokine quantification by ELISA revealed elevated TGF-β levels in GXM-treated cells and increased TNF-α levels in GXMGal-treated conditions. Furthermore, inhibition assays confirmed that these effects were reversed upon treatment with specific inhibitors.</div><div>The preliminary <em>in vitro</em> infection and treatment model indicates that the immunomodulatory effects of <em>C. neoformans</em> capsular components persist even in a distinct infection setting.</div><div>These findings reinforce the role of GXM as an immunosuppressive factor and GXMGal as an immunoprotective agent, suggesting that capsular components may differentially modulate host immune responses in various infectious contexts.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"271 ","pages":"Article 107849"},"PeriodicalIF":2.5,"publicationDate":"2025-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145129739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficacy assessment of a novel and two licensed Leishmania vaccines intended for dogs in an experimental hamster challenge model","authors":"Susanna Martorell ,&nbsp;Vickie King ,&nbsp;Sharath Rai ,&nbsp;Larry Alward ,&nbsp;Robert Berish ,&nbsp;Angela Weber ,&nbsp;Wanda Isaacson ,&nbsp;Alicia Urniza ,&nbsp;Jason Millership","doi":"10.1016/j.actatropica.2025.107848","DOIUrl":"10.1016/j.actatropica.2025.107848","url":null,"abstract":"<div><h3>Introduction and aim</h3><div>Visceral leishmaniasis is the most severe form of leishmaniasis affecting humans and canine species. Vaccination is the most cost-effective approach to disease control. Our aim is to compare an experimental vaccine candidate and two marketed vaccines (CaniLeish® and LetiFend®) with a control group using a hamster model.</div></div><div><h3>Methods</h3><div>The vaccine candidate formulation was based on two parasite antigenic components. The first is a purified fraction isolated from <em>Leishmania donovani</em> named fucose mannose ligand (FML) and the second is excretory/secretory protein (E/S) derived from a <em>L. donovani</em> culture. The proteins are formulated in a novel adjuvant system composed of three different adjuvants (CPG, Quil A and Cholesterol/Ethanol solution). The primary efficacy variables were parasitemia and clinical observations of skin lesions. The secondary efficacy variables were changes in body weight, parasite load and histopathology in target tissues.</div></div><div><h3>Results</h3><div>Compared to the control group, the novel vaccine candidate was superior to the other two vaccines in terms of efficacy based on lower parasitemia, parasite load in target tissues, less presence of amastigotes in the histopathology samples, fewer skin lesions and less bodyweight loss. These differences were statistically significant in the case of parasite load in blood (parasitemia), and target tissues (liver, skin, and spleen).</div></div><div><h3>Conclusion</h3><div>The novel vaccine candidate may have a higher efficacy benefit in the hamster model than CaniLeish® or Letifend® when compared to the control group. These results confirm the vaccine candidate as a potentially more efficacious alternative to the current commercially available vaccines against canine leishmaniasis.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"271 ","pages":"Article 107848"},"PeriodicalIF":2.5,"publicationDate":"2025-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145120068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial distribution of insecticide resistance in Aedes aegypti (Diptera: Culicidae) across Burkina Faso highlights strengthened resistance management strategies","authors":"Soumanaba Zongo ,&nbsp;Hyacinthe K. Toe ,&nbsp;Moussa W. Guelbeogo ,&nbsp;Antoine Sanou ,&nbsp;Alphonse Traore ,&nbsp;Madou Tapsoba ,&nbsp;Oumarou Tarpaga ,&nbsp;Prosper Tiaho ,&nbsp;Adama Gansane ,&nbsp;N’Falé Sagnon ,&nbsp;Brice Bicaba ,&nbsp;Moussa Namountougou","doi":"10.1016/j.actatropica.2025.107847","DOIUrl":"10.1016/j.actatropica.2025.107847","url":null,"abstract":"<div><div>Responses to recurrent dengue outbreaks rely on insecticide-based tools, effective use of which require understanding of insecticide resistance patterns. A nationwide study across all 13 regions of Burkina Faso was performed to assess countrywide resistance profiles of <em>Aedes aegypti</em> to major insecticide classes for informing decision-makers. WHO tube bioassays were performed under controlled conditions in a centralised location on <em>Ae. aegypti</em> adult females raised from eggs collected in each region. Mosquitoes were exposed to pyrethroids, carbamates, and organophosphates and mortality assessed 24-hours post-exposure. Fifty unexposed mosquitoes per region were genotyped for the F1534C, V1016I, and V410L kdr mutations, which confer resistance to pyrethroids, using melting curve qPCR analysis. <em>Ae. aegypti</em> populations from all 13 regions showed ubiquitous, and often strong resistance to deltamethrin. The F1534C mutation was the most prevalent with overall frequency of 0.89. The V1016I (0.25 - 0.58) and V410L (0.23 - 0.54) mutations were found at moderate and similar frequencies. Populations from seven regions showed resistance to bendiocarb. The resistance to pirimiphos-methyl and especially malathion was generally lower and less than half of the populations classified as resistant in each case. Across the four insecticides all 13 regions showed confirmed or suspected resistance to at least two insecticides and only eight of 13 showed any susceptibility, usually to an organophosphate. Thus, organophosphates, particularly malathion, appear the best overall option for control, and pyrethroid products are likely to show reduced efficacy. However, widespread multiple resistance across these three widely-used insecticide classes presents a challenge to resistance management, and newer alternative classes should be considered and testing built into monitoring programmes.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"271 ","pages":"Article 107847"},"PeriodicalIF":2.5,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145123931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Natural ecotope and feeding habits of Triatoma arthurneivai (Hemiptera: Reduviidae) in Espinhaço Mountain Range, State of Minas Gerais, Brazil","authors":"João Victor Leite Dias ,&nbsp;Maysa Farias de Almeida Araújo ,&nbsp;Alexandre Ferreira Righi ,&nbsp;Sílvia Ermelinda Barbosa ,&nbsp;Liléia Gonçalves Diotaiuti ,&nbsp;Herton Helder Rocha Pires","doi":"10.1016/j.actatropica.2025.107846","DOIUrl":"10.1016/j.actatropica.2025.107846","url":null,"abstract":"<div><div><em>Triatoma arthurneivai</em> Lent &amp; Martins 1940 is a rupicolous triatomine species only found in the Brazilian state of Minas Gerais. Little is known about its ecology, and the more recent records are restricted to adults captured in domiciles or light traps, with little or no information on its feeding habits or natural ecotopes. We report the very first finding of <em>T. arthurneivai</em> in nature and describe its feeding habits. After several unsuccessful attempts by our team to find the species in nature, we coincidentally received pictures of <em>T. arthurneivai</em> from two hiking biologists. Then, two field campaigns through an active search of triatomines were carried out in the surroundings of the city of Diamantina, close to the sight site, to find these insects. A total of 23 nymphs were captured among rocks of a rocky outcrop in a <em>campo rupestre</em> phytofisionomic landscape. The feeding behaviour was directly observed during the search when nymphs were seen blood-sucking on a treefrog of the species <em>Bokermannohyla alvarengai</em> (Bokermann, 1956) (Anura: Hylidae). Two other nymphs were subjected to molecular detection of blood sources in their intestinal content through DNA sequencing, which revealed the presence of <em>Tropidurus montanus</em> Rodrigues 1987 (Squamata: Tropiduridae) DNA. The feeding habits of <em>T. arthurneivai</em> in nature and under laboratory conditions reveal its eclecticism. Human disturbances in <em>campos rupestres</em>, including urbanisation, might favour the contact between these species and humans and/or synanthropic/domestic animals.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"271 ","pages":"Article 107846"},"PeriodicalIF":2.5,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145123892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Host-microbiota-parasite crosstalk: Gut microbiota dysbiosis exacerbates Leishmania infantum pathogenesis through altered immunity and glycerylphosphatide metabolism","authors":"Yuying Xiao ,&nbsp;Jinlei He ,&nbsp;Zheying Zhu ,&nbsp;Yanqin Zhao ,&nbsp;Xing Luo ,&nbsp;Jie Luo ,&nbsp;Xianguang Guo ,&nbsp;Dali Chen","doi":"10.1016/j.actatropica.2025.107845","DOIUrl":"10.1016/j.actatropica.2025.107845","url":null,"abstract":"<div><div>Visceral leishmaniasis, a deadly parasitic disease if untreated, urgently requires novel therapeutic strategies. The gut microbiota can modulate host immunity and disease susceptibility, but its specific impact on visceral leishmaniasis and the underlying molecular mechanisms are unclear. This study examined the interaction between intestinal microbiota and <em>Leishmania infantum</em> infection in a murine model, focusing on parasite load, immune response, and metabolic changes. Mice with induced intestinal dysbiosis were infected with L. <em>infantum</em> and monitored for five weeks. Post-euthanasia, murine liver and spleen were assessed for infection status, plasma was analyzed for antibodies, cytokines, and LC-MS/MS-based metabolomics, liver tissues were sequenced for transcriptomics, and fecal samples were analyzed by 16S rRNA sequencing. Results showed that L. <em>infantum</em> infection disrupted gut microbiota diversity, reducing taxa such as <em>Clostridia_UCG-014</em> and <em>Lachnospiraceae_NK4A136_group</em>, and inducing dysbiosis-related changes such as decreased <em>Muribaculaceae</em> and increased <em>Bacteroides</em> (<em>P</em>-values from 0.0018 to 0.0472). Dysbiotic mice had higher parasite loads in liver and spleen, more inflammatory lesions, lower serum IgG levels, and elevated Th1- and Th2-type cytokines. Transcriptomic and metabolomic analyses revealed dysregulated lipid metabolism (e.g., cholesterol and fatty acid biosynthesis) and increased glycerophospholipids, potentially supporting parasite membrane synthesis. These findings demonstrate that gut microbiota dysbiosis exacerbates L. <em>infantum</em> pathogenesis by altering host immunity and metabolic pathways, highlighting the potential for microbiota-targeted interventions to combat parasitic infections.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"271 ","pages":"Article 107845"},"PeriodicalIF":2.5,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145111694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring drug resistance and genetic polymorphisms in Iranian Trichomonas vaginalis isolates: focused on the ntr4Tv and ntr6Tv genes","authors":"Ahmad Abolghazi ,&nbsp;Faeze Foroughi-Parvar ,&nbsp;Mohammad Fallah ,&nbsp;Elham Kazemirad ,&nbsp;Mohammad Matini","doi":"10.1016/j.actatropica.2025.107844","DOIUrl":"10.1016/j.actatropica.2025.107844","url":null,"abstract":"<div><div>Urogenital trichomoniasis, caused by <em>Trichomonas vaginalis</em>, is primarily treated with nitroimidazoles. However, rising treatment failures and resistance have become a public health concern. The aim of the study was to evaluate the metronidazole susceptibility pattern of Iranian <em>T. vaginalis</em> isolates. This study analyzed 36 isolates, comprising 9 fresh clinical isolates obtained from consenting women attending gynecological clinics in Quds city, Tehran province, and 27 archival isolates from Hamadan province. Genetic characterization of the two nitroreductase genes, <em>ntr4_Tv</em> and <em>ntr6_Tv</em>, associated with metronidazole resistance, was performed in all isolates. Additionally, the archival isolates underwent in vitro drug susceptibility testing. The prevalence of trichomoniasis among women was 0.59% (95% CI: 0.51–0.67; 9/1525). Sequence analysis identified eight point mutations in <em>ntr4_Tv</em> and ten in <em>ntr6_Tv</em>, producing nine and six haplotypes, respectively. No genetic mutations associated with metronidazole resistance were identified in the analyzed isolates. Drug susceptibility testing indicated that the isolates were susceptible to metronidazole. Under aerobic conditions, 48-hour minimum lethal concentrations ranged from 1.6 to 25 μg/mL, with a mean of 9.6 ± 6.8 μg/mL. The prevalence of trichomoniasis in this region is significantly lower than global estimates, suggesting that alternative etiological agents should be prioritized in the differential diagnosis of vaginitis. Despite demonstrated metronidazole susceptibility among current isolates, robust surveillance integrating phenotypic drug testing and molecular resistance profiling is critical for sustained treatment efficacy and antimicrobial stewardship.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"271 ","pages":"Article 107844"},"PeriodicalIF":2.5,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145091102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantification and visualization of malaria-infected erythroblasts by imaging flow cytometry","authors":"Takashi Imai ,&nbsp;Shinya Miyazaki ,&nbsp;Yukiko Miyazaki ,&nbsp;Wataru Kagaya ,&nbsp;Mai Nakashima ,&nbsp;Kumpei Ito ,&nbsp;Miho Sase ,&nbsp;Misato Yoshioka-Takeda ,&nbsp;Chikako Shimokawa ,&nbsp;Kyoko Hayashi ,&nbsp;Tamasa Araki ,&nbsp;Takeshi Annoura ,&nbsp;Kentaro Itokawa ,&nbsp;Osamu Komagata ,&nbsp;Ngo-Thanh Ha ,&nbsp;Aoi Shimo ,&nbsp;Takashi Murakami ,&nbsp;Hajime Hisaeda","doi":"10.1016/j.actatropica.2025.107843","DOIUrl":"10.1016/j.actatropica.2025.107843","url":null,"abstract":"<div><div>Although malaria parasites are traditionally known to infect enucleated red blood cells, recent evidence—including our previous work—demonstrates their ability to invade nucleated erythroid precursors (erythroblasts). However, visualizing and quantifying parasitized erythroblasts (pEBs) <em>in vivo</em> remains challenging due to their rarity in peripheral blood and the limitations of existing techniques. In this study, we employed imaging flow cytometry (ImageStream) to identify and characterize pEBs in mice infected with <em>Plasmodium yoelii</em> 17XNL expressing green fluorescent protein and compared with conventional flow cytometry (FACS). At 14 days post-infection, splenic, bone marrow and peripheral blood cells were stained with antibodies against TER119 (erythroid marker) and MHC class I, which is expressed on nucleated host cells. To confirm the presence of nuclei, we also used Hoechst 33342 DNA staining. ImageStream analysis enabled simultaneous detection of GFP⁺TER119⁺MHC class I^hi Hoechst⁺ pEBs and morphological visualization. While no pEBs were detected in peripheral blood, a significant population was identified in the spleen and bone marrow. Importantly, quantification of pEB frequencies by ImageStream closely matched those obtained by FACS, validating the robustness of the imaging-based approach. Notably, ImageStream also revealed doublets and triplets involving pEBs and MHC class I⁺ cells, suggestive of erythroblastic islands or immunological interactions. Blebbing structures were occasionally observed, indicating apoptosis-like processes. These findings demonstrate that ImageStream offers a powerful platform for high-throughput, image-based detection of parasitized-erythroblasts in malaria. This approach may open new avenues for studying host–parasite interactions within hematopoietic tissues and their roles in parasite persistence and immune evasion.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"271 ","pages":"Article 107843"},"PeriodicalIF":2.5,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145085043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insights into AI-Driven malaria diagnosis: A systematic review with implications for Plasmodium knowlesi","authors":"Jia Ying Tiong ,&nbsp;Khairunnisa Hasikin ,&nbsp;Romano Ngui ,&nbsp;Paul C.S. Divis ,&nbsp;Chu Kiong Loo ,&nbsp;Khin Wee Lai ,&nbsp;Fei Wen Cheong ,&nbsp;Wan Yusoff Wan Sulaiman","doi":"10.1016/j.actatropica.2025.107842","DOIUrl":"10.1016/j.actatropica.2025.107842","url":null,"abstract":"<div><div><em>Plasmodium knowlesi</em> has emerged as a significant zoonotic malaria threat, particularly in Southeast Asia, where its incidence continues to rise. Timely and accurate diagnosis of its blood stages is critical for effective diagnosis and treatment, as disease severity and transmission dynamics vary across different stages. Microscopic examination is the gold standard for malaria diagnosis; however, it is labour-intensive and requires professional interpretation. This makes it prone to variability and possible misclassification, especially among morphologically identical <em>Plasmodium</em> species. Recent advancements in artificial intelligence (AI)-driven approaches, particularly deep learning, offer significant potential to assist microscopists in automating blood-stage identification, reducing diagnostic variability, and improving efficiency without replacing expert validation. However, the research on AI-based classification of <em>P. knowlesi</em> blood stages remains limited. This systematic review critically evaluates the datasets, preprocessing methods, and deep learning techniques used for <em>Plasmodium</em> blood-stage classification with a specific focus on <em>P. knowlesi.</em> Unlike previous reviews that primarily address species classification, this study provides an in-depth comparative analysis of AI-driven blood-stage identification, emphasizing the effectiveness of convolutional neural networks (CNNs), transfer learning, ensemble learning, and object detection models such as YOLO and Faster R-CNN. Additionally, this review highlights key challenges, including limited annotated datasets, class imbalance, and interpretability concerns that persist. Addressing these gaps through enhanced dataset curation, domain adaptation strategies, and explainable AI approaches will be crucial in advancing AI-driven <em>P. knowlesi</em> diagnostics.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"271 ","pages":"Article 107842"},"PeriodicalIF":2.5,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145079079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}