Microbial pathogenesis最新文献

{"title":"A quadruplex real-time fluorescent quantitative PCR detection method for identification and serotyping of Pasteurella multocida","authors":"Mengfei Zhao ,&nbsp;Wenqing Wu ,&nbsp;Wenbo Song ,&nbsp;Hao Yang ,&nbsp;Hanyuan Liu ,&nbsp;Rui Xie ,&nbsp;Xi Huang ,&nbsp;Jingwen Huang ,&nbsp;Lin Hua ,&nbsp;Huanchun Chen ,&nbsp;Bin Wu ,&nbsp;Zhong Peng","doi":"10.1016/j.micpath.2025.107889","DOIUrl":"10.1016/j.micpath.2025.107889","url":null,"abstract":"<div><div><em>Pasteurella multocida</em> is a zoonotic pathogen with the ability to infect a diverse range of hosts, including humans through contact with pets. Due to its diverse capsular serogroups, rapid and accurate identification, as well as serotyping, are essential for the effective prevention and control of infections caused by this bacterium. This study developed a quadruplex quantitative PCR (qPCR) method for the identification and serotyping of <em>P. multocida</em>, specifically differentiating capsular serogroups A, D, and F in cats and other hosts. Primers and probes targeted the <em>kmt1</em> gene (species-specific), <em>hyaD-hyaC</em> intergenic region (serogroup A), <em>dcbF</em> (serogroup D), and <em>fcbD</em> (serogroup F). The developed method demonstrated a detection limit of 1.7 copies/μL for the identification of <em>P. multocida</em> and 2.03, 11.24, and 14.52 copies/μL for the serotyping of capsular serogroups A, D, and F, respectively. The assay did not display cross-reactivity with other pathogens or different serogroups of <em>P. multocida</em>. Both the intra-assay and inter-assay coefficients of variation are below 1 %, highlighting the excellent reproducibility and specificity of the method. Applying this method, we examined 121 respiratory swabs from domestic cats, and 96 were tested positive for <em>P. multocida</em>. Among these positive samples, 66 were determined as capsular serogroup A, 1 as capsular serogroup D, and 24 as capsular serogroup F. The typing results exhibited high concordance with those obtained through bacterial isolation from the positive samples. The method developed in this study offers a rapid, accurate, and high-throughput approach for the identification and serotyping of <em>P. multocida</em> capsular serogroups A, D, and F. It serves as a powerful tool for advancing research into the pathogenic mechanisms of <em>P. multocida</em> and for implementing public health control measures.</div></div>","PeriodicalId":18599,"journal":{"name":"Microbial pathogenesis","volume":"207 ","pages":"Article 107889"},"PeriodicalIF":3.3,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588265","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":"Adaptive trade-offs between bacteriophage and antibiotic resistance in Salmonella Typhimurium","authors":"Song Zhang ,&nbsp;Juhee Ahn","doi":"10.1016/j.micpath.2025.107886","DOIUrl":"10.1016/j.micpath.2025.107886","url":null,"abstract":"<div><div>This study was designed to evaluate the phenotypic properties of PBST35-resistant <em>Salmonella enterica</em> subsp. <em>enterica</em> serovar Typhimurium in association with adaptive trade-offs between bacteriophage resistance and antibiotic resistance. Bacteriophage-insensitive <em>S</em>. <em>enterica</em> Typhimurium (BIST) variants were isolated and analyzed using the spot test, adsorption assay, and biofilm formation assay. The effects of bacteriophage and antibiotic combinations were evaluated using the disk diffusion assay, antibiotic susceptibility assay, and checkerboard assay to evaluate synergy. PBST35 bacteriophage showed a latent period of 10 min, a burst period of 50 min, and a burst size of 72 PFU/CFU. The swimming motility of BIST decreased significantly to 4 %, compared to 70 % in bacteriophage-sensitive <em>S</em>. <em>enterica</em> Typhimurium (BSST). BIST showed increased susceptibility to cefotaxime (CTX), ceftriaxone (CRO), meropenem (MEM), ciprofloxacin (CIP), levofloxacin (LEV), kanamycin (KAN), chloramphenicol (CHL), and sulfamethoxazole/trimethoprim (SXT). The MIC values of CTX, CIP, gentamicin (GEN), and polymyxin B (PMB) against BIST decreased by 2-fold, 1-fold, 2-fold, and 2-fold, respectively. The fractional inhibitory concentration (FIC) indices for BIST were 0.5 for CTX, 1.0 for CIP, 0.5 for GEN, and 0.5 for PMB. The sequential treatment of GEN and PBST35 reduced BSST biofilms by 87 % and BIST biofilms by 68 %. This study provides the potential of combining bacteriophages with antibiotics as a promising strategy to overcome resistance in bacteriophage-resistant strains and supports the development of integrated antimicrobial approaches to combat the growing threat of multidrug-resistant bacterial infections.</div></div>","PeriodicalId":18599,"journal":{"name":"Microbial pathogenesis","volume":"207 ","pages":"Article 107886"},"PeriodicalIF":3.3,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588264","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":"Deciphering cytokine Dynamics: Staged immune responses in acute otitis media","authors":"Yingying Chen ,&nbsp;Xiaolin Zhang ,&nbsp;Yang Liu ,&nbsp;Ziru Wei ,&nbsp;Maoli Yi ,&nbsp;Bo Li ,&nbsp;Yanfei Wang ,&nbsp;Hongchun Zhao ,&nbsp;Tihua Zheng ,&nbsp;Qingyin Zheng","doi":"10.1016/j.micpath.2025.107884","DOIUrl":"10.1016/j.micpath.2025.107884","url":null,"abstract":"<div><h3>Background</h3><div>Acute otitis media (AOM) is highly prevalent among preschool children and can lead to chronic otitis media or severe complications if untreated. The pathogenesis of AOM is closely tied to the host's immune response, yet the expression profile of cytokines, which mediate these responses, remains poorly defined.</div></div><div><h3>Purpose</h3><div>This study aims to identify cytokines involved in AOM immune responses and to elucidate their roles at different stages of the disease.</div></div><div><h3>Methods</h3><div>We induced AOM in mice by injecting nontypeable Haemophilus influenzae (NTHi) through the tympanic membrane. Middle ear tissues were collected for analysis. PCR Array and Protein Array identified cytokines at 6 and 12 hours (h) post-infection. qPCR and Luminex multiplex detection technology were then used to track cytokine expression at various key time points, allowing us to speculate on their roles in the immune process.</div></div><div><h3>Results</h3><div>PCR Array identified 13 cytokines with significant mRNA differences at 6 h. Protein Array identified 9 differentially expressed cytokines at 12 h qPCR tracked mRNA expression at key time points (6 h, 12 h, 1day (d), 2 d, 3 d and 7 d), revealing a total of 20 cytokines. Luminex detected 31 cytokines at key time points (12 h 1 d, 2 d and 5 d), 10 of which were previously mentioned. Cytokines were classified into three distinct categories according to their expression trends: early-phase (n = 13), progressive-phase (n = 20), and terminal-phase (n = 4) cytokines.</div></div><div><h3>Conclusion</h3><div>Cytokines play distinct and crucial roles at each stage of AOM, with potential interactions among those highly expressed in the same stage.</div></div>","PeriodicalId":18599,"journal":{"name":"Microbial pathogenesis","volume":"207 ","pages":"Article 107884"},"PeriodicalIF":3.3,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588266","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":"CsrR modulates biofilm formation of ST-17 GBS through the regulation of a novel adhesion factor, BapB","authors":"Wang Li ,&nbsp;Yali Fan ,&nbsp;Wenjie Zhu,&nbsp;Zheng Liang,&nbsp;Shuping Nie","doi":"10.1016/j.micpath.2025.107873","DOIUrl":"10.1016/j.micpath.2025.107873","url":null,"abstract":"<div><h3>Introduction</h3><div>The hypervirulent ST-17 clone of Group B <em>Streptococcus</em> (GBS) is a leading cause of neonatal invasive meningitis. The link between GBS biofilm formation and the ST-17 lineage is established, and the inhibition of GBS biofilm formation by CsrR involves the regulation of adhesins. However, the specific adhesins involved in biofilm formation in ST-17 GBS strains are unknown.</div></div><div><h3>Hypothesis/gap statement</h3><div>CsrR inhibits biofilm formation of ST-17 GBS through the regulation of specific adhesins.</div></div><div><h3>Aims</h3><div>To identify the adhesins contributing to biofilm formation in the ST-17 lineage.</div></div><div><h3>Methodology</h3><div>Comparative proteomics analyses of a strong biofilm-forming ST-17 strain and its <em>csrR</em> deletion mutant (<em>ΔcsrR</em>) were performed to identify the specific proteins involved in biofilm formation in ST-17 GBS. qPCR and biofilm formation assays were used to validate the proteomics analysis.</div></div><div><h3>Results</h3><div>A novel biofilm-associated protein, BapB, absent in non-biofilm-forming ST-17 GBS strains (e.g., COH1), was identified. Biofilm production was significantly attenuated in the <em>bapB</em> deletion mutant (<em>ΔbapB</em>), reducing GBS adherence to fibronectin and laminin.</div></div><div><h3>Conclusion</h3><div>BapB plays a crucial role in biofilm formation. It may be a potential target for design of new therapeutic approaches against GBS.</div></div>","PeriodicalId":18599,"journal":{"name":"Microbial pathogenesis","volume":"207 ","pages":"Article 107873"},"PeriodicalIF":3.3,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144575845","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":"Advancements in tuberculosis diagnostics: An update","authors":"Mainak Ghosh ,&nbsp;Monali Lahiri ,&nbsp;Aman Dalal,&nbsp;Kishan Kumar Parida,&nbsp;Nitin Pal Kalia","doi":"10.1016/j.micpath.2025.107843","DOIUrl":"10.1016/j.micpath.2025.107843","url":null,"abstract":"<div><div>Tuberculosis (TB) is one of the major life-threatening diseases caused by a single pathogen which has become a social menace owing to its high resistance. TB has even surpassed AIDS prior the COVID 19 pandemic. Every year the number of affected persons is increasing exponentially. In 2023 8.2 million new cases of TB were reported. There are various factors responsible for such infectivity rate of <em>Mycobacterium tuberculosis (Mtb</em>) including emergence of rapid resistant strains, treatment failure and lack of proper diagnosis. In order to combat the infection, early and effective treatment of the infection is very crucial. This calls for the existence of effective and point of care (POC) diagnostic tool for successful management of the disease. The conventional diagnostics includes staining, microscopy, tuberculin skin test and chest X ray. However, they have various limitations which increases the public threat. These tools lack the ease of transportation, less sensitive, time consuming and lack accuracy. To eliminate such limitations and bridge the gap associated with the proper diagnosis of disease, various biochemical, molecular, immunological diagnostic tools have come up in rescue of the infection. These modern tools are potent enough in characterizing <em>Mtb,</em> detect mutations correlated with the existing medications and ensure effective management. In this article we are focusing on modern diagnostic tools such as T-SPOT, artificial intelligence, electronic nose, RT PCR, TB LAM, CRISPR, biosensor-based detection techniques including the conventional techniques for detection of <em>Mtb</em> in clinical setup in resource limited healthcare facilities for comprehensive diagnosis of tuberculosis.</div></div>","PeriodicalId":18599,"journal":{"name":"Microbial pathogenesis","volume":"207 ","pages":"Article 107843"},"PeriodicalIF":3.3,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144575844","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":"TMT-based quantitative proteomics analysis reveals the inhibitory mechanism of CD-g-CS against the biofilm formation of Staphylococcus xylosus","authors":"Jinxin Ma ,&nbsp;Qiumei He ,&nbsp;Liting Lai ,&nbsp;Zhongbin Zhang ,&nbsp;Guoying Huang ,&nbsp;Guangquan Li ,&nbsp;Xiangyu Kong ,&nbsp;Jinqing Chen ,&nbsp;Ling Tang ,&nbsp;Wenyou Ding ,&nbsp;Lihua Chen ,&nbsp;Wenya Ding","doi":"10.1016/j.micpath.2025.107831","DOIUrl":"10.1016/j.micpath.2025.107831","url":null,"abstract":"<div><div>Chitosan-grafted β-cyclodextrin (CD-g-CS) serves as an excipient combining drug delivery capacity with antimicrobial activity. Previous studies have demonstrated that the CD-g-CS nanoformulations have significant inhibitory effects on bacterial biofilms, although the mechanism of action remains unclear. Consequently, the present study used tandem mass tag (TMT)-based quantitative proteomics coupled with quantitative PCR (qPCR) to investigate the mechanism underlying CD-g-CS-mediated inhibition of <em>Staphylococcus xylosus</em> (<em>S. xylosus</em>) biofilm formation at the protein level. The results showed that 903 proteins were identified to be altered in <em>S. xylosus</em> treated with CD-g-CS, of which 430 were down-regulated and 500 were up-regulated. Bioinformatics analysis revealed that these differentially expressed proteins (DEPs) have different molecular functions and are involved in different molecular pathways. CD-g-CS affected the functional pathways of <em>S. xylosus</em> in terms of ribosomes, phosphotransferase system (PTS), tricarboxylic acid (TCA) cycle, and nitrate respiration. These pathways affected the stability and morphology of biofilms, which in turn interfere with biofilm formation. These results provide a critical excipients for future development of anti-biofilm pharmaceutical formulations, offering novel solutions to combat biofilm infections.</div></div>","PeriodicalId":18599,"journal":{"name":"Microbial pathogenesis","volume":"207 ","pages":"Article 107831"},"PeriodicalIF":3.3,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144584344","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":"Comparison of total IgG and neutralizing antibody responses to a novel trivalent recombinant Mannheimia haemolytica vaccine containing serotype 6","authors":"Aslı Balevi ,&nbsp;Ayşegül İlban ,&nbsp;Ali Uslu ,&nbsp;Emine Eda Toslak ,&nbsp;Zafer Sayın ,&nbsp;Gökçenur Sanioğlu Gölen ,&nbsp;Yasemin Karyeyen ,&nbsp;Ayten Gök ,&nbsp;Canan Kebabcıoglu ,&nbsp;Osman Erganis","doi":"10.1016/j.micpath.2025.107875","DOIUrl":"10.1016/j.micpath.2025.107875","url":null,"abstract":"<div><div><em>Mannheimia haemolytica</em> (<em>M. haemolytica</em>) causes significant losses in livestock, but cross-protection between serotypes is limited. Current commercial vaccines primarily target serotypes 1 (S1) and 2 (S2) despite the increasing incidence of serotype 6 (S6) infections. While leukotoxin (LKT) is a common vaccine target, serotype-1 specific antigen (SSA-1) is often overlooked. Furthermore, neutralizing antibody (nAb) titers, crucial for evaluating vaccine efficacy, are not routinely measured. This study aimed to develop a trivalent vaccine targeting S1, S2, and S6 using recombinant LKT (rLKT) and rSSA-1, and to evaluate total IgG and nAbs responses following vaccination in the murine model. Three <em>M. haemolytica</em> strains (S1, S2, and S6) with diverse phenotypic characteristics were selected. A host specificity protein J (250 kDa) was identified in the S6 strain grown in Todd-Hewitt broth. This protein caused widespread bleeding in experimental mouse groups, raising considerations for its inclusion in future vaccine formulations. A trivalent vaccine was prepared by different serotypes (S1, S2, and S6), rLKT, rSSA-1, and Montanide™ ISA 206 VG adjuvant. Mice were vaccinated twice at 21-day intervals. Total IgG and nAb titers were measured using in-house ELISAs and Vero cell neutralization assays, respectively. Total IgG revealed the highest antibody responses against S2 pellet and S6 supernatant antigens. The result of nAb titers in the vaccinated mice; was 1/80 (log10^1.9) against three pellets (S1, S2, and S6), and supernatant protein (S6) in contrast to 1/40 (log10^1.6) against other supernatant proteins (S1, S2). The vaccine demonstrated an odds ratio of 0.97. Although total IgG titers against S1 were lower compared to other serotypes, nAb increases were similar across all serotypes, highlighting the importance of measuring nAb titers in addition to total IgG for a comprehensive vaccine evaluation. Challenge studies further corroborated the stimulation of nAbs. The trivalent vaccine effectively stimulated both total IgG and nAb responses against all three serotypes in mice, suggesting its potential for broad protection against <em>M. haemolytica.</em></div></div>","PeriodicalId":18599,"journal":{"name":"Microbial pathogenesis","volume":"207 ","pages":"Article 107875"},"PeriodicalIF":3.3,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144584343","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":"Amoebicidal activity of Plantago lanceolata extract and expression of three genes in Acanthamoeba castellanii trophozoites","authors":"Bulent Kaynak ,&nbsp;Gulizar Aydogdu ,&nbsp;Zeynep Koloren ,&nbsp;Panagiotis Karanis","doi":"10.1016/j.micpath.2025.107863","DOIUrl":"10.1016/j.micpath.2025.107863","url":null,"abstract":"<div><div>This study investigated the therapeutic potential of an ethanolic leaf-stem extract from Turkish <em>Plantago lanceolata</em> against <em>Acanthamoeba castellanii</em>. The extract exhibited amoebicidal activity against <em>A. castellanii</em> trophozoites at varying concentrations (125, 62.5, 31.25, 15.625, 7.81, 3.9 and 1.95 mg/mL). The cytotoxicity of the extract in HeLa cells was investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The DNA protective potential of the extracts against DNA damage was investigated. The phytochemical constituents of the extract were identified and characterized using Gas Chromatography-Mass Spectrometry (GC-MS). RT-qPCR analysis quantified the transcriptional modulation of oxidative stress-responsive genes (SOD, CAT) and the pseudocyst formation marker CSII in <em>A. castellanii</em> trophozoites following exposure to <em>P. lanceolata</em> extract. The viability and number of <em>Acanthamoeba</em> trophozoites were evaluated through hemocytometer counting coupled with the Trypan Blue exclusion technique. IC₅₀ values of <em>A. castellanii</em> trophozoites were 2.6, 4.2 and 14.45 mg/mL at the 72nd, 48th and 24th hours, respectively. MTT viability assays demonstrated dose-dependent cytotoxicity in HeLa cells following 72-h exposure to <em>P. lanceolata</em> extract (12.5, 6.25, 3.125, 1.562, 0.781, 0.391, 0.195 mg/mL), yielding an IC₅₀ of 0.85 mg/mL. The extract exhibited protective effects against DNA damage induced by hydroxyl radicals at 15.625, 7.81 and 3.9 mg/mL concentrations. Furthermore, it was determined that the extract showed a strong inhibitory effect on CSII and almost as much effect on CAT and SOD genes as the specific inhibitors of CAT and SOD genes. The obtained data indicate that this extract may serve as a potential therapeutic agent for both the prevention and treatment of acanthamoebiasis.</div></div>","PeriodicalId":18599,"journal":{"name":"Microbial pathogenesis","volume":"207 ","pages":"Article 107863"},"PeriodicalIF":3.3,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144572392","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":"Silver nanoparticle treatment partially restores antibiotic activity by reducing the number of isolates with antibiotic-resistant genes in cows with mastitis","authors":"Claudio H. Mejia-Ruiz ,&nbsp;Ekaterina Nefedova ,&nbsp;Nikolay N. Shkil ,&nbsp;Carlos R. Romo-Quiñonez ,&nbsp;Alexey Pestryakov ,&nbsp;D. Garibo ,&nbsp;Nina Bogdanchikova","doi":"10.1016/j.micpath.2025.107871","DOIUrl":"10.1016/j.micpath.2025.107871","url":null,"abstract":"<div><div>In recent years, intensive use of antibiotics has led to bacterial strains developing resistance, which decreases their effectiveness in disease treatments. One of the approaches for combating resistance is combinational therapies, which consist of the use of antibiotic resistance inhibitors in combination with antibiotics. Our group is developing a new approach, consisting of therapy with AgNPs as an inhibitor, without combination with antibiotics. The aim of this work was to study <em>in vivo</em> on 744 cows with serous mastitis and in relation to 31 antibiotics: (1) the capacity of cow therapy with AgNPs to modulate <em>mecA</em> (<em>S. aureus</em>), <em>blaGES</em> and <em>blaDHA</em> (<em>E. coli</em>) resistance genes, and (2) compare the results with those obtained for therapy with antibiotic medicine. The data obtained after AgNP therapy showed a 40.3 % and 54.5 % reduction in antibiotic-resistant <em>S. aureus</em> and <em>E. coli</em> isolate numbers, respectively, whereas they increased by 48.9 % and 114.9 % after antibiotic therapy. The percentage of isolates with detected drug-resistant genes decreased on average by 22.7 % after AgNP treatment, while they increased on average by 36.9 % after antibiotic therapy. This decrease of resistance genes in isolates caused by AgNP therapy is the fifth route of combating bacterial resistance with AgNPs, in addition to four routes revealed by our group. These findings provide further insight into the origins of the capacity of AgNP therapy to combat resistance.</div></div>","PeriodicalId":18599,"journal":{"name":"Microbial pathogenesis","volume":"207 ","pages":"Article 107871"},"PeriodicalIF":3.3,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144575857","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":"In vitro antiviral activity of chitosan and curcumin-loaded chitosan nanoparticles against virulent Newcastle disease virus isolates","authors":"Gopika Gopalakrishnan ,&nbsp;P.M. Deepa ,&nbsp;R. Rajasekhar ,&nbsp;Jess Vergis ,&nbsp;K.C. Bipin ,&nbsp;R.L. Rathish ,&nbsp;A. Janus","doi":"10.1016/j.micpath.2025.107870","DOIUrl":"10.1016/j.micpath.2025.107870","url":null,"abstract":"<div><div>Newcastle disease virus (NDV) is a highly contagious avian pathogen requiring effective antiviral strategies. This study evaluated the <em>in vitro</em> antiviral efficacy of chitosan nanoparticles (CNPs) and curcumin-loaded chitosan nanoparticles (Cur-CNPs) against virulent NDV isolates from poultry in Kerala, India. Screening of 40 suspected flocks by reverse transcription polymerase chain reaction (RT-PCR) targeting the fusion (F) gene revealed a 12.5 % positivity rate. Sequencing confirmed virulent strains based on amino acid motifs at the F protein cleavage site. Two isolates, L2/MIB/PKD/23 and B3/MIB/PKD/23, were propagated in embryonated chicken eggs, and their virulence was confirmed through hemagglutination, hemagglutination inhibition, and mean death time assays. Virus adaptation to cell culture demonstrated higher replication efficiency in chicken embryo fibroblast cells.</div><div>CNPs and Cur-CNPs were synthesised via ionic gelation and characterized by spectroscopic and microscopic techniques. Cytotoxicity assessment determined minimum non-cytotoxic concentrations of 187.5 μg/mL for CNPs and 1.47 μg/mL for Cur-CNPs. Antiviral activity, evaluated by MTT assay, demonstrated the highest protection with Cur-CNPs (0.75:1 ratio), achieving 44.18 % and 47.12 % protection for the two isolates. Viral titre reduction assays indicated a decrease of 3.00 log10 in TCID50 and a twofold reduction in hemagglutination titres. Quantitative real-time PCR confirmed significant viral load reductions (p &lt; 0.001) with Cur-CNPs compared to CNPs.</div><div>These findings indicate that Cur-CNPs exhibit strong antiviral activity against NDV and may serve as potential alternatives to conventional antiviral agents for Newcastle disease control.</div></div>","PeriodicalId":18599,"journal":{"name":"Microbial pathogenesis","volume":"207 ","pages":"Article 107870"},"PeriodicalIF":3.3,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144575847","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}