Memorias do Instituto Oswaldo Cruz最新文献

{"title":"Detection of immunogenic protein components in excretion/secretion products of Acanthamoeba T5 using polyclonal antibodies.","authors":"Lissette Retana-Moreira, Elizabeth Abrahams-Sandí, Marco Ruiz-Campos, Johan Alvarado-Ocampo, Julián Castro, Jacob Lorenzo-Morales, Giovanni Sáenz-Arce, Antonio Osuna","doi":"10.1590/0074-02760240190","DOIUrl":"10.1590/0074-02760240190","url":null,"abstract":"<p><strong>Background: </strong>Acanthamoeba is a free-living amoeba widely distributed, responsible for keratitis and granulomatous amoebic encephalitis. The presence of virulence factors in its excretion/secretion products has been demonstrated. Characterisation of these products, including the determination of immunogenic protein components using polyclonal antibodies, could be the basis for the development of new diagnostic tools and help to understand aspects related to its pathogenesis.</p><p><strong>Objectives: </strong>To identify immunogenic protein components in Acanthamoeba conditioned medium (ACM) and extracellular vesicles (EVs) using polyclonal anti-Acanthamoeba antibodies produced in the laboratory and to evaluate the effect of these antibodies in adhesion and cytopathic effect.</p><p><strong>Methods: </strong>Excretion/secretion products were obtained after the axenic culture of a potentially pathogenic environmental Acanthamoeba T5 isolate. The presence of immunogenic components in lysates of trophozoites, ACM and EVs was determined using polyclonal anti-Acanthamoeba antibodies produced in Wistar rats. Proteomic analyses to identify the immunogenic protein components in ACM and EVs were included. Experiments to evaluate the effect of polyclonal anti-Acanthamoeba antibodies in adhesion and cytopathic effect in vitro were also performed in Vero cells.</p><p><strong>Findings: </strong>Protein recognition by anti-Acanthamoeba antibodies in lysates, ACM and EVs was demonstrated, and these components were identified using proteomics. Decreases in adhesion and cytopathic effect after the preincubation of trophozoites with antibodies, prior to the contact with cells, were observed.</p><p><strong>Main conclusion: </strong>The development of polyclonal antibodies, capable of recognising proteins related to pathogenesis in ACM and EVs, and with significant effects in adhesion, provides an important tool for the search for new therapeutic and diagnostic targets in infections caused by Acanthamoeba.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240190"},"PeriodicalIF":2.5,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12158434/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144275321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Challenges in developing new tuberculosis vaccines.","authors":"Gabriela Sadigurschi, Maria Cristina Caetano Kuschnir, Ewerton Alves Portela Dos Santos, Bruno Rangel Antunes da Silva, Celia Menezes Cruz Marques, Raissa Coelho de Andrade, Clarice Monteiro Vianna, Danillo Gonçalves de Barros, Mariana Torres Mazzi, Elvira Alonso Lago, Eliane Matos Dos Santos, Maria de Lourdes de Sousa Maia","doi":"10.1590/0074-02760240236","DOIUrl":"10.1590/0074-02760240236","url":null,"abstract":"<p><p>Tuberculosis (TB) is a preventable and curable disease caused by the bacillus Mycobacterium tuberculosis. In 2022, according to the World Health Organisation (WHO), TB was the second leading cause of death worldwide caused by a single infectious agent, after coronavirus disease (COVID-19). Brazil is ranked among the 30 countries with the highest TB burden. Currently, the neonatal Bacillus Calmette-Guérin (BCG) is the only vaccine against TB and offers significant efficacy against disseminated and meningeal disease in children. However, BCG has a limited efficacy in preventing adult-type cavitary TB, reinforcing the need for a new effective vaccine against pulmonary TB. There are currently over 22 TB vaccines under evaluation in clinical trials worldwide. Despite significant advancements, several challenges persist in developing and producing an effective TB vaccine. These include understanding the immune mechanisms that confer protection against M. tuberculosis, identifying immune correlates of protection, defining immune responses in BCG-vaccinated individuals, establishing efficacy endpoints for TB vaccine trials, and ensuring vaccine safety and effectiveness in individuals with human immunodeficiency virus (HIV), among other obstacles. Therefore, this study aims to explore the key obstacles in developing new TB vaccines and potential strategies to overcome them.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240236"},"PeriodicalIF":2.5,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12158433/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144275320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Parasitological cure and clinical benefits of benznidazole treatment in patients from the Jequitinhonha Valley, MG, Brazil, with recent chronic infection by Trypanosoma cruzi II.","authors":"Marta de Lana, Lourena Tomazelli Suave, Júlio César Santoro de Oliveira Assis, Girley Francisco Machado de Assis, Matheus Marques Milagre, Glaucia Diniz Alessio, Renato Afonso Salgado, Olindo Assis Martins-Filho, Pedro Albajar-Viñas, Rosália Morais Torres","doi":"10.1590/0074-02760240229","DOIUrl":"10.1590/0074-02760240229","url":null,"abstract":"<p><strong>Background: </strong>The treatment of the early chronic phase of Chagas disease (CD) may result in high rates of parasitological cure, which may be associated with clinical benefits.</p><p><strong>Objectives: </strong>To evaluate children with CD from the Jequitinhonha Valley, MG, Brazil, treated with benznidazole (BZ), employing classic and alternative methodologies.</p><p><strong>Methods: </strong>Before and after treatment, nine individuals were examined by haemoculture, polymerase chain reaction (PCR), conventional enzyme-linked immunosorbent assay (ELISA), electrocardiogram, echocardiogram, and thoracic and gastrointestinal X-ray. Eight individuals were in the indeterminate clinical form of CD, and one was in the mild cardiac form. After treatment, all individuals were re-evaluated periodically for 4-26 years using the same methodologies cited and anti-live trypomastigotes antibodies by flow-cytometry-FC-ALTA and quantitative PCR (qPCR).</p><p><strong>Findings: </strong>The cure rate by the classic cure criteria was 33.33%. By the alternative cure criteria using FC-ALTA and qPCR, the rates of cure were 50% and 78%, respectively. Post-treatment clinical evaluations revealed stability in 5/9 and discrete clinical evolution in 4/9 individuals.</p><p><strong>Main conclusions: </strong>It was demonstrated the effectiveness of BZ treatment in recent chronic infections of CD with low or higher rates of parasitological cure according to the cure criterion used after long-term follow-up. The clinical status of the individuals remained stable or evolved slowly, suggesting clinical benefits from BZ treatment.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240229"},"PeriodicalIF":2.5,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12147451/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144225882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Use of Brazilian flora as the main source of new antimalarials: a systematic review.","authors":"Ana Rafaela Antunes Porto, Isabela de Brito Duval, Luisa Vitor Braga do Amaral, Izabela da Silva Oliveira, João Gabriel Acioli de Siqueira, Bruno Araújo de Albuquerque, Maria Alice Guarini Rocha, Gabriela Gomes Monteiro Lemos, Marcelo Eduardo Cardozo, José Bryan da Rocha Rihs, Ricardo Toshio Fujiwara, Ana Laura Grossi de Oliveira, Ramayana Morais de Medeiros Brito, Lilian Lacerda Bueno","doi":"10.1590/0074-02760240123","DOIUrl":"10.1590/0074-02760240123","url":null,"abstract":"<p><p>Plants represent an important source of compounds for treating malaria, highlighting the rich biodiversity of Brazilian flora as a vital resource for developing new, effective antimalarial drugs. The present study sought to shed light on the search for new compounds with antimalarial activity obtained from the Brazilian flora. In this sense, a systematic review was conducted using screening techniques based on \"The Preferred Reporting Items for Systematic Reviews and Meta-Analysis\" (PRISMA) protocol. Most of the plants collected in the studies were from the Amazon Rainforest, north of Brazil. Most of the isolated compounds were from the Apocynaceae family and the alkaloids were the main compounds isolated with significant antiplasmodial activity, followed by flavonoids and phenolic compounds. The Brazilian flora can source many compounds with potential antimalarial activity that can challenge Plasmodium drug resistance. However, new studies are still needed to elucidate the natural compounds activity for future application in Malaria treatment.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240123"},"PeriodicalIF":2.5,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12147452/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144225883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Miltefosine analogues with comparable antileishmanial activity and significantly reduced macrophage cytotoxicity.","authors":"Lais Alonso, Laís Flávia Nunes Lemes, George E Magoulas, Brenda de Lucena Costa, Rodrigo Saar Gomes, Miriam Leandro Dorta, Maria Laura Bolognesi, Luiz Antonio Soares Romeiro, Theodora Calogeropoulou, Antonio Alonso","doi":"10.1590/0074-02760240219","DOIUrl":"10.1590/0074-02760240219","url":null,"abstract":"<p><strong>Background: </strong>Miltefosine (MIL) is the only oral drug approved for leishmaniasis treatment, but its use is limited by gastrointestinal toxicity. Novel alkylphospholipid analogues may provide safer and more effective alternatives.</p><p><strong>Objectives: </strong>This study aimed to assess the antileishmanial activity, cytotoxicity, and membrane interactions of three MIL analogues TC387, TC388, and TC437 against Leishmania amazonensis.</p><p><strong>Methods: </strong>Antileishmanial and cytotoxic activities were evaluated in L. amazonensis, J774.A1 macrophages, and erythrocytes. Membrane interactions were characterized using spin-label electron paramagnetic resonance (EPR) spectroscopy.</p><p><strong>Findings: </strong>TC387, TC388, and TC437 demonstrated EC50 values of 10-16 µM for intracellular amastigotes, compared to 17 µM for MIL, with selectivity indices (SI) ranging from 43-163, significantly higher than MIL's SI of 5. EPR data revealed that the analogues increased membrane protein dynamics and caused greater disruption at the lipid-protein interface of parasite membranes relative to MIL. This disruption likely enhances pore formation, ion leakage, and reactive oxygen species (ROS) production, leading to parasite death.</p><p><strong>Main conclusions: </strong>The MIL analogues TC387, TC388, and TC437 exhibited superior SI and comparable or slightly enhanced antileishmanial activity relative to MIL, along with very low hemolytic potential. These findings support further investigation of these analogues as promising oral therapeutic candidates for leishmaniasis.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240219"},"PeriodicalIF":2.5,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12113339/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144174065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anti-PGL-I seropositivity and development of leprosy in contacts: a comprehensive analysis of sociodemographic determinants, genetic susceptibility, and exposure characteristics to Mycobacterium leprae.","authors":"Eyleen Nabyla Alvarenga Niitsuma, Isabela de Caux Bueno, Gabriel da Rocha Fernandes, Mery Natali Silva Abreu, Francisco Carlos Félix Lana","doi":"10.1590/0074-02760240061","DOIUrl":"10.1590/0074-02760240061","url":null,"abstract":"<p><strong>Background: </strong>Leprosy is an infectious disease that remains hyperendemic in several Brazilian regions. Patient contacts face a higher risk for infection and illness, which can subsequently contribute to the persistence of the disease.</p><p><strong>Objective: </strong>This study investigates the risk factors associated with anti-phenolic glycolipid-I (anti-PGL-I) seropositivity and leprosy development among contacts of leprosy patients in a highly endemic region.</p><p><strong>Methods: </strong>A cohort of 629 contacts from the Almenara microregion, Minas Gerais, Brazil, was followed from 1998 to 2018. Our research group assessed risk factors, including sociodemographic determinants, bacillus exposure, and genetic susceptibility.</p><p><strong>Findings: </strong>Analysis revealed that living with a multibacillary (MB) leprosy patient [odds ratio (OR): 3.01, 95% confidence interval (CI): 1.02-8.86] and with a patient with grade II disabilities (OR: 4.43, 95% CI: 1.08-18.1) significantly increased the likelihood of anti-PGL-I seropositivity among asymptomatic contacts. Risk factors for leprosy included living with a patient in a shared residence (OR: 2.84, 95% CI: 1.21-6.67) and blood relation to the patient (OR: 2.56, 95% CI: 1.18-5.54). Notably, 98% of contacts who developed leprosy had lived with more than one patient.</p><p><strong>Main conclusions: </strong>Clinical characteristics of index patients play a critical role in infection risk among contacts. Leprosy progression appears to depend on genetic susceptibility, type of contact, and extent of bacillus exposure.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240061"},"PeriodicalIF":2.5,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12113343/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144174061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Single nucleotide polymorphisms in IFN-gamma, TNF-alpha, IL-6, IL-10, and TGF-beta in pulmonary and extrapulmonary tuberculosis in the State of Ceará, northeastern Brazil.","authors":"Roberta Dos Santos Silva Luiz, Thales Alves Campelo, Caroliny Soares Silva, Lucas de Lima Nogueira, Soraya de Oliveira Sancho, Ana Karolliny Alves da Silva, Cristiane Cunha Frota, Filipe Anibal Carvalho-Costa","doi":"10.1590/0074-02760240147","DOIUrl":"10.1590/0074-02760240147","url":null,"abstract":"<p><strong>Background: </strong>Single nucleotide polymorphisms (SNP) in genes encoding cytokines influence tuberculosis (TB) outcomes.</p><p><strong>Objectives: </strong>To characterise genotypes of the SNPs IFN-gamma +874 T > A, TNF-alpha -308 G > A, IL-6 -174 G > C, IL-10 -1082A > G, TGF-beta codon 10 T > C, and TGF-beta codon 25 G > C in patients with pulmonary (PTB) and extrapulmonary TB (EPTB).</p><p><strong>Methods: </strong>82 PTB and 45 EPTB cases were compared, concerning genotype distribution of the mentioned SNPs, characterised via sequence-specific primer polymerase chain reaction (PCR).</p><p><strong>Findings: </strong>Regarding IFN-gamma +874 T > A, AA genotype was the most frequent in both groups, TA was more frequent in PTB and TT in EPTB, with no statistical significance. For SNP TNF-alpha -308 G > A, GG was more frequent in both groups of patients. Regarding the IL-6 -174 G > C polymorphism, GG predominated in both groups, while CG and GG were significantly more frequent in patients with PTB and EPTB, respectively. Concerning IL-10 -1082 A > G, AA predominated in both PTB and EPTB. Concerning TGF-beta codon 10 T > C, CC predominated in PTB while TC predominated in EPTB, but the differences were not statistically significant. Genotype GG of TGF-beta codon 25 G > C predominated among PTB and EPTB patients.</p><p><strong>Main conclusions: </strong>Except for IL-6, the genotype profile could not differentiate PTB and EPTB. Hence, the studied SNPs are not significantly associated with the extrapulmonary involvement of TB.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240147"},"PeriodicalIF":2.5,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12084083/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144111032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Concomitant occurrence of chronic Schistosoma mansoni infection and chronic colitis restore immune imbalance and dysbiosis leading to protection against intestinal colitis and schistosome egg-induced intestinal fibrosis.","authors":"You-Ren Lin, Long Yin Lam, Chun-Ming Chang, Ho Yin Pekkle Lam","doi":"10.1590/0074-02760240045","DOIUrl":"https://doi.org/10.1590/0074-02760240045","url":null,"abstract":"<p><strong>Background: </strong>Schistosomiasis is one of the most devastating tropical diseases in developing countries and is usually misdiagnosed with colitis because the prevalence of co-occurrence of both diseases is high. Previously, infection of Schistosoma japonicum cercariae has been shown to provide immediate protection against dextran sodium sulphate (DSS)-induced acute colitis in mice models. Studies using synthesised peptides or soluble proteins from parasites also revealed similar protection against colitis. However, most of these studies were done within a short timeframe, which cannot completely represent the actual situation where natural infection of Schistosoma or colitis is usually chronic.</p><p><strong>Objectives: </strong>This study aims to investigate how chronic schistosomiasis affects chronic intestinal inflammation.</p><p><strong>Methods: </strong>Mice were infected with Schistosoma mansoni and induced simultaneously with chronic colitis. The symptoms and severity of intestinal inflammation and fibrosis were investigated by disease activity index, histology, enzyme-linked immunosorbent assay (ELISA), and quantitative polymerase chain reaction (qPCR). Furthermore, immune analysis by ELISA and qPCR and microbiome analysis by 16S rDNA sequencing were done to investigate the underlying mechanism.</p><p><strong>Findings: </strong>Concomitant occurrence of chronic schistosomiasis and chronic colitis significantly alleviated colitis symptoms, lessened intestinal inflammation, and reduced egg-induced fibrosis. Further analysis revealed an alternation of the intestinal immunity and gut microbiome community in mice with both diseases, which could be the potential reason for this outcome.</p><p><strong>Main conclusions: </strong>Our results represent a mechanism of how schistosomiasis and chronic intestinal inflammation affect each other.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240045"},"PeriodicalIF":2.5,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12051921/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144034601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lessons from the \"Urbanorum spp.\" controversy: a supposed parasite and the need for scientific rigor and quality research in Latin America.","authors":"Diego Fernando Echeverry, Manuel Andrés Sarria, Gloria Inés Palma","doi":"10.1590/0074-02760240144","DOIUrl":"https://doi.org/10.1590/0074-02760240144","url":null,"abstract":"<p><strong>Background: </strong>Despite insufficient parasitological and clinical evidence, infections attributed to a putative protozoan named \"Urbanorum spp.\" have been associated with gastrointestinal disease and treated with anti-parasitic drugs.</p><p><strong>Objectives: </strong>This study aimed to clarify the nature of \"Urbanorum spp.\" and provide guidance for health and biomedical professionals encountering this structure in human stool, emphasising the importance of rigor and quality in biomedical research.</p><p><strong>Methods: </strong>Coprological analyses were employed to detect intestinal parasites, lipids, and \"Urbanorum spp.\" in 249 samples. Samples positive for \"Urbanorum spp.\" underwent staining with trichrome, acid-fast, and Sudan IV and contrasted with positive controls. Examination with polarised light microscopy and a fragility test using ethanol were conducted.</p><p><strong>Findings: </strong>Of the tested samples, 19.4%, 2.5% and 1.3% were positive for intestinal parasites, lipids, and \"Urbanorum spp.\" respectively. Following trichrome and acid-fast staining, few \"Urbanorum spp.\" structures remained intact and exhibited no discernible eukaryotic characteristics; Sudan IV stain, polarized light microscopy and fragility test approaches indicated a cholesterol-based content.</p><p><strong>Main conclusions: </strong>\"Urbanorum spp.\" is not a protozoan parasite; therefore, antiparasitic drugs are unwarranted. This structure should be identified as lipid-based material and investigated for possible malabsorption syndrome. Rigorous scientific standards were missed in related publications and peer review, contributing to the spread of this pseudoparasitism case.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240144"},"PeriodicalIF":2.5,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12051917/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144027730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of dengue virus infection on the cytoadherence of Plasmodium vivax-infected erythrocytes.","authors":"Maria Geuziane Soares da Cruz, Rafaella Oliveira Dos Santos, Maria Gloria Teixeira Sousa, Fabio Tm Costa, Marcus Vinícius Guimarães de Lacerda, Stefanie Costa Pinto Lopes, Pritesh Lalwani","doi":"10.1590/0074-02760240185","DOIUrl":"https://doi.org/10.1590/0074-02760240185","url":null,"abstract":"<p><strong>Background: </strong>Coinfections of Plasmodium parasites and the dengue virus have been linked to severe disease in some patients. The interactions between these two pathogens, particularly their effects on disease progression, highlight the clinical importance of understanding the mechanisms underlying the potential synergistic effects.</p><p><strong>Objectives: </strong>The primary objective of this study was to investigate the adhesion dynamics of Plasmodium vivax-infected erythrocytes (Pv-iRBCs) in the presence of dengue virus (DENV) infection. By examining the interaction between these pathogens, the study aimed to provide insights into how coinfections might influence disease severity and progression.</p><p><strong>Methods: </strong>HepG2 cells were infected with DENV to observe changes in adhesion receptors and Pv-iRBCs adhesion capacity. Experiments using trypsin-treated Pv-iRBCs and UV-inactivated DENV dissected the adhesion process. Small molecule inhibitors were used to assess innate activation. ICAM-1 expression and its functional significance was quantified using a monoclonal anti-ICAM-1 antibody.</p><p><strong>Findings: </strong>We noted a significant increase in cytoadherence of Pv-iRBCs following DENV infection compared to mock conditions. Both trypsin treatment of Pv-iRBCs and UV inactivation of DENV led to a reduction in cytoadherence, underscoring their impact on the adhesion process. Notably, DENV infection induces an innate immune activation upregulating ICAM-1 on the cell surface and blocking with a monoclonal anti-ICAM-1 antibody significantly reduced the cytoadherence of Pv-iRBCs.</p><p><strong>Main conclusions: </strong>Elevated ICAM-1 levels on DENV-permissive cells may not only trap parasites within several niches but also contribute to endothelial and haematological disturbances in individuals with coinfections. Further research is required to fully elucidate the roles of cytoadherence and immune activation in the pathogenesis of dengue and malaria coinfections.</p>","PeriodicalId":18469,"journal":{"name":"Memorias do Instituto Oswaldo Cruz","volume":"120 ","pages":"e240185"},"PeriodicalIF":2.5,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12039924/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144009057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}