Microbes and Infection最新文献

{"title":"Schistosoma heamatobium tetraspanins TSP-2 and TSP-6 induce Dendritic Cells maturation, cytokine production and T helper cells differentiation in vitro","authors":"Angela Silvano ,&nbsp;Javier Sotillo ,&nbsp;Marta Cecchi ,&nbsp;Alex Loukas ,&nbsp;Mireille Ouedraogo ,&nbsp;Astrid Parenti ,&nbsp;Fabrizio Bruschi ,&nbsp;Maria Gabriella Torcia ,&nbsp;Valentina D Mangano","doi":"10.1016/j.micinf.2024.105439","DOIUrl":"10.1016/j.micinf.2024.105439","url":null,"abstract":"<div><div>Urogenital schistosomiasis caused by <em>Schistosoma haematobium</em> is a major cause of disability in endemic areas. Despite its socio-economic burden, no vaccine exists and the parasite's immunobiology remains underexplored. Genome annotation has revealed over 40 different genes encoding tetraspanins, transmembrane proteins with known immunomodulatory properties in other plathelminthes. This study investigated the role of <em>Sh</em>-TSP-2, <em>Sh</em>-TSP-6 and <em>Sh</em>-TSP-23, which are expressed in the parasite's tegument and extracellular vesicles (EVs). Immature dendritic cells (DCs) from unexposed healthy donors were stimulated with these proteins to evaluate maturation maker expression and cytokine production. Also, pre-activated T CD4⁺ cells were stimulated with the DCs supernatant to assess cytokine gene expression. <em>Sh</em>-TSP-2 and <em>Sh</em>-TSP-6 induced maturation markers and cytokine production in DCs: <em>Sh</em>-TSP-2 increased CD80 and CD83 levels and the concentration of both pro-inflammatory (IL-6, TNF) and regulatory (IL-10) cytokines, while <em>Sh</em>-TSP-6 increased the production of IL-6. Moreover, supernatants from <em>Sh</em>-TSP-2 stimulated DCs induced the expression of Th1 (IFNɣ) and regulatory (IL-10) cytokines in CD4⁺ T cells, while <em>Sh-</em>TSP-6 induced Th2 (IL-4, IL-13) cytokine expression. These results provide evidence that <em>S. haematobium</em> tetraspanins modulate the response of human DCs and CD4⁺ T cells <em>in vitro,</em> and support <em>Sh</em>-TSP-2 as a promising vaccine candidate.</div></div>","PeriodicalId":18497,"journal":{"name":"Microbes and Infection","volume":"27 3","pages":"Article 105439"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142644004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of anti-tuberculosis treatment on respiratory tract microbiome in pulmonary tuberculosis","authors":"Druti Hazra ,&nbsp;Kiran Chawla ,&nbsp;Fayaz S.M. ,&nbsp;Vitali Sintchenko ,&nbsp;Rahul Magazine ,&nbsp;Elena Martinez ,&nbsp;Akhilesh Pandey","doi":"10.1016/j.micinf.2024.105432","DOIUrl":"10.1016/j.micinf.2024.105432","url":null,"abstract":"<div><div>The growing evidence has underscored the significance of interactions between the host and microbiota in respiratory health, presenting a novel perspective on disease management. Yet, comprehension of the respiratory microbiome shifts before and after anti-tuberculosis treatment is limited. This study compares respiratory microbiome profiles in untreated tuberculosis (UTB) and completed TB treatment (CTB) cases with healthy controls, using 16S rRNA sequencing on sputum samples. Significant reduction in sputum microbial alpha diversity was observed in both TB groups when compared to healthy controls (P &lt; 0.05). Beta diversity analysis showed distinct clustering (P &lt; 0.05). Linear discriminant analysis revealed an abundance of potentially pathogenic bacterial genera like <em>Haemophilus, Pseudomonas</em>, and <em>Mycobacterium</em> in the UTB group, while <em>Streptococcus, Rothia</em>, and <em>Neisseria</em> dominated in CTB samples. Healthy sputum microbiomes were enriched with <em>Prevotella, Fusobacterium, Porphyromonadaceae_unclassified,</em> <em>and</em> <em>Peptostreptococcus</em>. Moreover, predicted bacterial functional pathways showed significant differences among the three groups, mainly related to nutrient metabolism.</div><div>These findings indicated significant microbial dysbiosis in sputum samples recovered from patients with pulmonary TB with an elevated presence of potentially pathogenic bacteria, depletion of beneficial genera, and downregulation of several essential metabolic pathways. Further exploration of respiratory microbiome-based diagnostic biomarkers and their role in targeted treatment strategies in tuberculosis is warranted.</div></div>","PeriodicalId":18497,"journal":{"name":"Microbes and Infection","volume":"27 3","pages":"Article 105432"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142469726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolution and zoonotic risk of O1:K1 and O2:K1 avian pathogenic Escherichia coli","authors":"Eun-Jin Ha ,&nbsp;Seung-Min Hong ,&nbsp;Kang-Seuk Choi ,&nbsp;Hyuk-Joon Kwon","doi":"10.1016/j.micinf.2024.105462","DOIUrl":"10.1016/j.micinf.2024.105462","url":null,"abstract":"<div><div>The O1 and O2 serogroups of avian pathogenic <em>E. coli</em> (APEC) and human extraintestinal pathogenic <em>E. coli</em> (huExPEC) are closely related, but their evolutionary relationships need to be further elucidated. This study classified nineteen O1 and O2 APEC into <em>rpoB</em> sequence types (RSTs) and compared them with reference huExPEC using molecular prophage typing, virulence and antibiotic resistance gene profiling, and comparative genomics. Most O1:K1 and O2:K1 APEC (73.7 %) were classified as RST46-1 and RST47-9. RST47-9 is unique to Korean O1 APEC and likely derives from RST46-1 APEC. The six APEC showed high genome coverage/identity with the Korean RST46-1 huExPEC. Based on RST network and comparative genomics, we hypothesized that the O1 antigen first appeared in RST19-1 and O2 in RST24-1 <em>E. coli</em> in humans. Then, O1 and O2-antigen horizontally transferred to human RST46-1, where a unique K1 capsule (K1-<em>cps</em>) first appeared. The Korean APEC and huExPEC share evolutionary CRISPR spacers but differ in molecular antibiograms and prophage contents. Thus, RST46-1 huExPEC transmitted and evolved in poultry. The zoonotic risks remain unknown, but the substantial virulence of the RST46-1 APEC indicates that the reverse zoonotic risk of huExPEC in poultry is alarming.</div></div>","PeriodicalId":18497,"journal":{"name":"Microbes and Infection","volume":"27 3","pages":"Article 105462"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142791753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gingivitis- and periodontitis-associated microbiota in bovine deciduous incisor teeth – A preliminary study","authors":"Juliana Vaccari ,&nbsp;Ana C. Borsanelli ,&nbsp;Flávia R.F. Athayde ,&nbsp;Júlia R. Saraiva ,&nbsp;Thamiris N.M. Ramos ,&nbsp;Iveraldo S. Dutra","doi":"10.1016/j.micinf.2024.105468","DOIUrl":"10.1016/j.micinf.2024.105468","url":null,"abstract":"<div><div>As ruminants are frequently affected by periodontal diseases, understanding their microbial communities is crucial. In this pilot study, we analyzed subgingival biofilm samples of young cattle across different states: clinically healthy (n = 5), gingivitis (n = 5), and periodontitis (n = 5) using 16S rRNA gene sequencing and co-occurrence network analysis. The findings revealed that Proteobacteria was the predominant phylum across all conditions, with Fusobacteriota constituting 27.6 % of the microbiota in periodontitis-affected sites. In healthy sites, <em>Moraxella</em> (21.11 %), <em>Neisseria</em> (13.16 %), and <em>Lautropia</em> (7.69 %) were the predominant genera; in gingivitis-affected sites, the leading genera were <em>Neisseria</em> (23.65 %), <em>Moraxella</em> (18.95 %), and <em>Conchiformibius</em> (10.79 %); and in periodontitis sites, <em>Caviibacter</em> (19.78 %), <em>Moraxella</em> (16.13 %), and <em>Fusobacterium</em> (7.56 %) were most prevalent. Richness and dissimilarity analyses did not show significant differences across the clinical states, but differences were found between gingivitis and periodontitis sites (p = 0.01) in diversity. The co-occurrence networks highlighted significant variances in the central phyla across the phenotypes, with a higher number of positive interactions observed in periodontitis-affected sites. Consequently, this study demonstrated that the microbiota associated with periodontitis in young cattle exhibits greater diversity compared to gingivitis. Notably, in the deciduous dentition of cattle, the genera <em>Caviibacter</em> and <em>Moraxella</em> are pivotal in the context of periodontitis and periodontal health, respectively.</div></div>","PeriodicalId":18497,"journal":{"name":"Microbes and Infection","volume":"27 3","pages":"Article 105468"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142915278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Screening and in silico characterization of prophages in Helicobacter pylori clinical strains","authors":"Rute Ferreira ,&nbsp;Graça Pinto ,&nbsp;Eva Presa ,&nbsp;Mónica Oleastro ,&nbsp;Catarina Silva ,&nbsp;Luís Vieira ,&nbsp;Cláudia Sousa ,&nbsp;Diana P. Pires ,&nbsp;Ceu Figueiredo ,&nbsp;Luís D.R. Melo","doi":"10.1016/j.micinf.2024.105429","DOIUrl":"10.1016/j.micinf.2024.105429","url":null,"abstract":"<div><div>The increase of antibiotic resistance calls for alternatives to control <em>Helicobacter pylori</em>, a Gram-negative bacterium associated with various gastric diseases. Bacteriophages (phages) can be highly effective in the treatment of pathogenic bacteria. Here, we developed a method to identify prophages in <em>H. pylori</em> genomes aiming at their future use in therapy. A polymerase chain reaction (PCR)-based technique tested five primer pairs on 74 clinical <em>H. pylori</em> strains. After the PCR screening, 14 strains most likely to carry prophages were fully sequenced. After that, a more holistic approach was taken by studying the complete genome of the strains. This study allowed us to identify 12 intact prophage sequences, which were then characterized concerning their morphology, virulence, and antibiotic-resistance genes. To understand the variability of prophages, a phylogenetic analysis using the sequences of all <em>H. pylori</em> phages reported to date was performed. Overall, we increased the efficiency of identifying complete prophages to 54.1 %. Genes with homology to potential virulence factors were identified in some new prophages. Phylogenetic analysis revealed a close relationship among <em>H. pylori</em>-phages, although there are phages with different geographical origins. This study provides a deeper understanding of <em>H. pylori</em>-phages, providing valuable insights into their potential use in therapy.</div></div>","PeriodicalId":18497,"journal":{"name":"Microbes and Infection","volume":"27 3","pages":"Article 105429"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142378063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bad company? The pericardium microbiome in people investigated for tuberculous pericarditis in an HIV-prevalent setting","authors":"Georgina Nyawo ,&nbsp;Charissa C. Naidoo ,&nbsp;Benjamin G. Wu ,&nbsp;Benjamin Kwok ,&nbsp;Jose C. Clemente ,&nbsp;Yonghua Li ,&nbsp;Stephanie Minnies ,&nbsp;Byron Reeve ,&nbsp;Suventha Moodley ,&nbsp;Thadathilankal-Jess John ,&nbsp;Sumanth Karamchand ,&nbsp;Shivani Singh ,&nbsp;Alfonso Pecararo ,&nbsp;Anton Doubell ,&nbsp;Charles Kyriakakis ,&nbsp;Robin Warren ,&nbsp;Leopoldo N. Segal ,&nbsp;Grant Theron","doi":"10.1016/j.micinf.2024.105434","DOIUrl":"10.1016/j.micinf.2024.105434","url":null,"abstract":"<div><h3>Background</h3><div>The site-of-disease microbiome and predicted metagenome were evaluated in a cross-sectional study involving people with presumptive tuberculous pericarditis. We also explored the interaction between C-reactive protein (CRP) and the microbiome.</div></div><div><h3>Methods</h3><div>People with effusions requiring diagnostic pericardiocentesis (n=139) provided pericardial fluid for sequencing and blood for CRP measurement.</div></div><div><h3>Results</h3><div>Pericardial fluid microbiota differed in β-diversity among people with definite (dTB, n=91), probable (pTB, n=25), and non- (nTB, n=23) tuberculous pericarditis. dTBs were <em>Mycobacterium-, Lacticigenium-,</em> and <em>Kocuria-</em>enriched vs. nTBs. HIV-positive dTBs were <em>Mycobacterium-, Bifidobacterium-</em>, <em>Methylobacterium-</em>, and <em>Leptothrix</em>-enriched vs. HIV-negative dTBs. HIV-positive dTBs on ART were <em>Mycobacterium</em>- and <em>Bifidobacterium</em>-depleted vs. those not on ART. dTBs exhibited enrichment in short-chain fatty acid (SCFA) and mycobacterial metabolism pathways vs. nTBs. Additional non-pericardial involvement (pulmonary infiltrates) was associated with <em>Mycobacterium</em>-enrichment and <em>Streptococcus</em>-depletion. <em>Mycobacterium</em> reads were in 34 % (31/91) of dTBs, 8 % (2/25) of pTBs and 17 % (4/23) nTBs. People with CRP above (vs. below) the median value had different β-diversity (<em>Pseudomonas</em>-depleted). No correlation was found between enriched taxa in dTBs and CRP.</div></div><div><h3>Conclusions</h3><div>Pericardial fluid microbial composition varies by tuberculosis status, HIV (and ART) status and dTBs are enriched in SCFA-associated taxa. The clinical significance, including mycobacterial reads in nTBs and pTBs, requires evaluation.</div></div>","PeriodicalId":18497,"journal":{"name":"Microbes and Infection","volume":"27 3","pages":"Article 105434"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142624005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TGEV nonstructural protein ORF3b upregulates the expression of SLA-DR at the transcriptional level in monocyte-derived porcine dendritic cells","authors":"Hang Liu ,&nbsp;Mengyao Ma ,&nbsp;Xinhao Jia ,&nbsp;Mengwei Qian ,&nbsp;Bo Pang ,&nbsp;Muzi Li ,&nbsp;Honglei Zhang ,&nbsp;Shijie Ma ,&nbsp;Lanlan Zheng","doi":"10.1016/j.micinf.2024.105437","DOIUrl":"10.1016/j.micinf.2024.105437","url":null,"abstract":"<div><div>Transmissible gastroenteritis virus (TGEV) is a porcine intestinal pathogenic coronavirus that can cause acute intestinal diseases in pigs, especially in suckling piglets under two weeks of age, with a mortality rate of 100 %. Dendritic cells (DCs) are important antigen-presenting cells (APCs) that are essential for the initiation and modulation of immune responses in animals. In this study, we used monocyte-derived porcine DCs as an in vitro model of APCs to further study the pathogenic mechanism of TGEV. Our results demonstrated that TGEV successfully replicates in monocyte-derived porcine DCs, whereas UV-inactivated TGEV failed to infect these cells. Importantly, TGEV infection of DCs led to significant upregulation of swine leukocyte antigen II DR (SLA-DR), a key molecule in the major histocompatibility complex class II (MHC-II) family. We further demonstrated that the ORF3b nonstructural protein of TGEV significantly enhances SLA-DR expression at the transcriptional level in porcine DCs. This study provides new insights into the pathogenic mechanisms of TGEV.</div></div>","PeriodicalId":18497,"journal":{"name":"Microbes and Infection","volume":"27 3","pages":"Article 105437"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142624011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The SARS-CoV-2 antibody-dependent enhancement façade","authors":"Jeremia M. Coish ,&nbsp;Lori A. MacNeil ,&nbsp;Adam J. MacNeil","doi":"10.1016/j.micinf.2024.105464","DOIUrl":"10.1016/j.micinf.2024.105464","url":null,"abstract":"<div><div>Antibody-dependent enhancement (ADE) is an immunological paradox whereby sensitization following a primary viral infection results in the subsequent enhancement of a similar secondary infection. This idiosyncratic immune response has been established in dengue virus infections, driven by four antigenically related serotypes co-circulating in endemic regions. Several coronaviruses exhibit antibody-mediated mechanisms of viral entry, which has led to speculation of an ADE capacity for SARS-CoV-2, though <em>in vivo</em> and epidemiological evidence do not currently support this phenomenon. Three distinct antibody-dependent mechanisms for SARS-CoV-2 entry have recently been demonstrated: 1. FcR-dependent, 2. ACE2-FcR-interdependent, and 3. FcR-independent. These mechanisms of viral entry may be dependent on SARS-CoV-2 antibody specificity; antibodies targeting the receptor binding domain (RBD) typically result in Fc-dependent and ACE2-FcR-interdependent entry, whereas antibodies targeting the N-terminal domain can induce a conformational change to the RBD that optimizes ACE2-receptor binding domain interactions independent of Fc receptors. Whether these antibody-dependent entry mechanisms of SARS-CoV-2 result in the generation of infectious progenies and enhancement of infection has not been robustly demonstrated. Furthermore, ADE of SARS-CoV-2 mediated by antigenic seniority remains a theoretical concern, as no evidence suggests that SARS-CoV-2 imprinting blunts a subsequent immune response, contributing to severe COVID-19 disease.</div></div>","PeriodicalId":18497,"journal":{"name":"Microbes and Infection","volume":"27 3","pages":"Article 105464"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142813831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revisiting the concept of giant viruses","authors":"Jônatas Santos Abrahão","doi":"10.1016/j.micinf.2024.105467","DOIUrl":"10.1016/j.micinf.2024.105467","url":null,"abstract":"<div><div>Giant viruses have fascinated the scientific community due to their immense particles and extensive genomes. A significant surge of interest in the field has been observed over the past 20 years following the discovery of mimiviruses, the first amoeba-infecting viruses described. However, with the discovery of new amoeba viruses and those from other protists, the concept of \"giant viruses\" has become increasingly controversial in the scientific literature. This commentary revisits the historical and conceptual foundations of the term \"giant virus\" and explores its implications for virology.</div></div>","PeriodicalId":18497,"journal":{"name":"Microbes and Infection","volume":"27 3","pages":"Article 105467"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142895386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proteolytic activity of secreted proteases from pathogenic leptospires and effects on phagocytosis by murine macrophages","authors":"Thais A. Amamura ,&nbsp;Daniella dos S. Courrol ,&nbsp;Angela S. Barbosa ,&nbsp;Ildefonso A. Silva-Junior ,&nbsp;Tiago F. da Silva ,&nbsp;Leonardo M. Midon ,&nbsp;Mario C. Cruz ,&nbsp;Marcos B. Heinemann ,&nbsp;Rosa M. Chura-Chambi ,&nbsp;Ligia Morganti ,&nbsp;Lourdes Isaac","doi":"10.1016/j.micinf.2025.105469","DOIUrl":"10.1016/j.micinf.2025.105469","url":null,"abstract":"<div><div>Leptospirosis is a zoonosis caused by spirochete <em>Leptospira.</em> Pathogenic leptospires evade the Complement System, enabling their survival upon contact with normal human serum <em>in vitro</em>. In a previous study, we demonstrated that proteases secreted by pathogenic leptospires cleave several Complement proteins, including C3 and the opsonins C3b and iC3b. We hypothesize that these <em>Leptospira</em> proteases, such as thermolysin and leptolysin, may decrease the phagocytic activity of murine peritoneal macrophages. We observed decreased amounts of CR3 and CR4 using flow cytometry when these cells were treated with supernatant from the culture of pathogenic leptospires (SPL) for 24 h. Through confocal microscopy, we observed a reduction in TLR2, CD11b, and CD206 (mannose receptor) levels when these cells were treated with SPL or recombinant thermolysin for 24 h. Furthermore, opsonins such as C3b/iC3b deposited on the surface of pathogenic leptospires were clearly degraded in the presence of recombinant thermolysin or recombinant leptolysin. Consequently, when opsonized bacteria and macrophages were previously incubated with these proteases, phagocytic activity was diminished. These observations lead us to suggest that proteases secreted by pathogenic leptospires could degrade opsonins present in normal serum or deposited on the bacterial membrane, as well as cleave or inhibit macrophage surface molecules. Therefore, these proteases could interfere with the recognition and internalization by murine macrophages, favoring the spread of leptospires in the host.</div></div>","PeriodicalId":18497,"journal":{"name":"Microbes and Infection","volume":"27 3","pages":"Article 105469"},"PeriodicalIF":2.6,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142951207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}