Search Results (234)

A novel lytic bacteriophage, XAN_XB1, was isolated from hospital wastewater through host bacterial enrichment and evaluated for its potential in controlling multidrug-resistant Stenotrophomonas maltophilia infections. Transmission electron microscopy revealed that XAN_XB1 has a long tail, possessing an icosahedral head of ~80 nm in diameter and a tail measuring ~150 nm in length. It produced clear plaques of 0.5–1 mm on host bacterial lawns. Host range analysis demonstrated its ability to infect multiple multidrug-resistant S. maltophilia isolates. Biological characterization showed that the phage is chloroform-insensitive, retains strong lytic activity across a wide temperature (4–60 °C) and pH (3.0–10.0) range, and achieves more rapid host suppression under higher multiplicity of infection (MOI). Whole-genome sequencing determined a ~47 kb double-stranded DNA genome encoding 64 predicted open reading frames, with no known virulence or antibiotic resistance genes. Phylogenetic analysis of MCP and terminase large subunit sequences placed XAN_XB1 in a unique Caudoviricetes, with ANI values below the 95% ICTV threshold verifying its status as a novel phage species. The XAN_XB1 therapy significantly alleviates S. maltophilia infection-induced severe pulmonary inflammatory lesions, high mortality, elevated serum inflammatory factors and massive pulmonary bacterial colonization in male BALB/c mice, confirming its favorable therapeutic effect on such infections. Collectively, these results reveal that is an efficacious candidate for therapeutic development against S. maltophilia infections. Full article

S. suis is a prominent zoonotic pathogen responsible for diseases such as arthritis in piglets, swine septicemia, and meningitis. The emergence of multi-drug resistance (MDR) underscores the urgent need for the development of novel antibacterial strategies. In this context, a systematic evaluation of the antibacterial potential of the bacteriophage lytic enzyme Ply900 was conducted in this study, along with an analysis of its domain functions and an in vivo study of its therapeutic dynamics. Ply900 exhibits potent in vitro lytic activity against multiple bacteria, including Streptococcus suis, Streptococcus agalactiae, and Staphylococcus aureus. Notably, it possesses broad biochemical stability, with tolerance to diverse environmental conditions. In a mouse model of S. suis serotype 2 SC19 infection, both the direct Ply900 treatment group and the triple therapy group achieved effective eradication of S. suis, with markedly improved survival rates. The remaining bacteria remained susceptible to Ply900, with no evidence of induced resistance development. Mechanistic analysis revealed that the SH3B domain of Ply900 enhances targeted cleavage efficiency by binding synergistically to peptidoglycan with the CHAP domain, with CYS-34, HIS-59, and ASP-28 serving as key amino acid sites for Ply900’s cleavage activity. Collectively, these findings lay the foundation for the potential dual applications of the lysin Ply900, both in the clinical treatment of S. suis infections and in the prevention and control of these pathogenic bacteria in livestock farming. Full article

Coxsackievirus B3 (CVB3) is a picornavirus that causes systemic inflammatory diseases including myocarditis, pericarditis, pancreatitis, and meningoencephalitis. We have previously reported that CVB3 induces mitochondrial fission and mitophagy while inhibiting lysosomal degradation by blocking autophagosome-lysosome fusion. This promotes the release of virus-laden mitophagosomes from host cells as infectious extracellular vesicles (EVs), enabling non-lytic viral egress. Transient receptor potential vanilloid 1 (TRPV1), a heat and capsaicin-sensitive cation channel, regulates mitochondrial dynamics by inducing mitochondrial membrane depolarization and fission. In this study, we found that TRPV1 activation by capsaicin dramatically enhances CVB3 egress from host cells via EVs. Released EVs revealed increased levels of viral capsid protein VP1, mitochondrial protein TOM70, and fission protein phospho-DRP1. Moreover, these EVs were enriched in heat shock protein HSP70, suggesting its role in facilitating infectious EV release from cells. Furthermore, TRPV1 inhibition with capsazepine and SB-366791 significantly reduced viral infection in vitro. Our in vivo studies also found that SB-366791 significantly mitigates pancreatic damage and reduces viral titers in a mouse model of CVB3 pancreatitis. Given the lack of understanding regarding factors that contribute to diverse clinical manifestations of CVB3, our study highlights capsaicin and TRPV1 as potential exacerbating factors that facilitate CVB3 dissemination via mitophagy-derived EVs. Full article

An unmet challenge in managing breast cancer is treatment failure due to resistance to apoptosis-inducing chemotherapies. Thus, it is important to identify novel non-apoptotic therapeutic agents. Several non-apoptotic programmed cell death pathways utilize specific cellular signaling events to trigger lytic and pro-inflammatory cell death, examples of which are pyroptosis and necroptosis. Our study illustrates that ophiobolin A (OpA) is an anti-cancer agent that triggers lytic cell death in breast cancer cells, including triple-negative breast cancer (TNBC). This study reveals that OpA induces typical pyroptosis-like characteristics, including cellular swelling, plasma membrane rupture, GSDMD cleavage, and release of cytokines in breast cancer cells. However, the additional involvement of RIPK1 and induction of RIPK3 clustering in select cell lines suggest that multiple pathways may be triggered upon OpA treatment. The induction of pro-inflammatory cell death suggests potential applications for OpA in cancer treatment. Full article

Many biomedical applications require a detailed understanding of the action of antimicrobial peptides on biological membranes. The cationic hemolytic peptide melittin, a major component of European honey bee (Apis mellifera) venom, is considered a model for elucidating lipid–protein interactions that are important for the function of biological systems. Here, we address the surface properties of human erythrocytes and rat liver mitochondrial membranes under in vitro melittin treatment. These membranes are negatively charged at neutral pH and represent primary targets of melittin’s effects in the onset of inflammatory diseases. The correlation between the functional activity of membrane systems and their surface electrical charge was assessed using microelectrophoresis, hemolysis assays, membrane transport measurements, lipid peroxidation analysis, and fluorescence microscopy. A mechanistic hypothesis for the divergent effects of sub-lytic, pre-pore doses of melittin on erythrocytes and mitochondria is discussed. At low concentrations, melittin interacts electrostatically with erythrocyte membranes, resulting in altered proton transport through the Band 3 protein. Melittin also induces changes in erythrocyte morphology and malondialdehyde content, as well as aggregation of mitochondrial vesicles. The electrokinetic mechanism of melittin action, associated with membrane stability, provides a novel perspective on its potential relevance to biomedical applications. Full article

This study evaluated hepatic pathological and phenotypic alterations, along with the inflammatory response, following sequential dengue virus (DENV) infection in Callithrix penicillata, a relevant model for human endemic scenarios. Twenty-six animals were initially infected subcutaneously with DENV-3. Thirteen were euthanized between 1 and 7 days post-infection (dpi) to assess the acute phase, and up to 60 dpi for the convalescent phase. The remaining animals received a secondary DENV-2 infection two months later. Liver samples underwent histopathological and immunohistochemical analysis. Viral antigens were identified in hepatocytes, Kupffer cells, and Councilman bodies. Observed liver changes included apoptosis, lytic necrosis, midzonal inflammation, Kupffer cell hyperplasia and hypertrophy, sinusoidal dilation, and hemosiderin deposition. Both primary and secondary infections increased activated macrophages, NK cells, S-100 protein, and B lymphocytes. Primary infection was associated with elevated CD4⁺ T cells, IFN-γ, TGF-β, IL-10, and Fas expression, whereas secondary infection induced higher IFN-γ, TNF-α, IL-8, Fas, and VCAM levels. These findings mirror hepatic alterations in severe human dengue cases and underscore the role of direct viral effects and immune dysregulation in liver injury. The results support C. penicillata as a suitable non-human primate model for studying DENV pathogenesis. Full article

Cancer involves uncontrolled cell growth, leading to tumor formation, and remains a major cause of mortality worldwide. Colorectal cancer (CRC) arises from abnormal proliferation of colon glandular epithelial cells. We assessed the cytotoxic and molecular effects of lithium carbonate (Li₂CO₃) and lithium chloride (LiCl) in two CRC cell lines (HCT-116 and SW-620) and a non-tumorigenic line (CRL-1790). Viability assays revealed dose-dependent cytotoxicity, with HCT-116 being the most sensitive cell line (IC₅₀: 8.14 mM for Li₂CO₃). Notably, long-term lithium exposure reduced proliferation, lowering colony-forming efficiency (CFE) and a phenotypic shift from holoclones to meroclones and paraclones, indicating diminished self-renewal capacity. Minimal membrane damage was observed (LDH assay), suggesting non-lytic mechanisms consistent with apoptosis. TUNEL and Annexin-V/IP assays confirmed apoptosis in >40% of cells, without caspase-3 cleavage, suggesting a caspase-independent pathway. PARP-1 cleavage occurred only in SW-620 cells. Western blotting exposed cell-specific modulation of GSK-3β: increased inactive form (p-Ser9) in CRC cells and decreased in CRL-1790 cells, implying differential disruption of Wnt/β-catenin signaling. c-Myc levels remained unchanged, suggesting possible post-translational regulatory effects. Overall, these findings indicate that lithium salts selectively reduce CRC cell viability, impair stem-like characteristics, and induced caspase-independent apoptosis. Therefore, we expand the proof of concept of the potential of lithium-based compounds as low-toxicity adjuvant agents in colorectal cancer therapy. Full article

The short peptide AlaGluAspLeu (AEDL) stimulates shoot and root development in Nicotiana tabacum. Growing tobacco in the presence of AEDL was found to induce autophagy and programmed cell death, as demonstrated using immunodetection of the autophagy marker ATG8 and cytochrome c in the cytoplasm, as well as the detection of DNA breaks using the TUNEL assay. A detailed study of the ultrastructure of Nicotiana tabacum root cells grown in the presence of AEDL using transmission electron microscopy revealed fundamental structural differences from control cells. Control cells contained only lytic vacuoles, while in the presence of AEDL, tobacco root meristem cells contained predominantly protein-storing vacuoles and amyloplasts with numerous starch granules in the stroma. Characteristic types of phagophores were identified, forming numerous small autophagosomes with cytoplasmic regions, multivesicular bodies, or concentric membranes, possibly with cytoskeletal elements. Expression of autophagy protein genes revealed a decrease in TOR expression, which promoted autophagy activation and prevented ATG13 phosphorylation. ATG8 gene expression significantly increased in the presence of the AEDL peptide. Schematic diagrams of autophagy processes in root cells of control plants and those grown in the presence of AEDL are presented. Based on these data, it was concluded that stimulation of tobacco plant development in the presence of the AEDL peptide at a concentration of 10⁻⁷ M occurs due to the activation of metabolic processes and autophagy. Moreover, the synthesis of metabolites exceeds the required amount of nutrients, which accumulate in vacuoles and leucoplasts. Full article

Capsular polysaccharides are critical virulence factors of Klebsiella pneumoniae, enabling the bacterium to evade host immune recognition and exacerbate infection. Phage-derived depolymerases, which specifically degrade these capsular polysaccharides, are increasingly recognized as a highly promising strategy for the treatment of bacterial infections. In the present study, we isolated and characterized a lytic Klebsiella pneumoniae phage, named phiTH1, and sequenced its genome. The K30-type capsular polysaccharide was identified as the receptor for phiTH1 infection. A tail fiber protein with a pectate lyase domain, Dop5, was then recognized as a potential K30-type depolymerase. Therefore, the recombinant protein Dop5 was expressed in Escherichia coli and purified, and its in vitro capsular depolymerase activity was demonstrated. Further, by using a murine aspiration pneumonia model induced by K30-type Klebsiella pneumoniae TH1, we found that Dop5 protected 80% of mice from lethal challenge with Klebsiella pneumoniae. After Dop5 treatment, the pathological damage in multiple organs of mice was alleviated, the bacterial load was reduced, and serum levels of inflammatory cytokines and complement C3 decreased, along with a significant reduction in the pathological score of the lungs. Hence, this study revealed the potential of the depolymerase Dop5 for the treatment of Klebsiella pneumoniae infections. Full article

Hepatocellular carcinoma (HCC) is the main leading cause of cancer-related deaths. Treatments for advanced HCC include multikinase inhibitors (Sorafenib or Lenvatinib), with limited response rates and serious side effects, or immunotherapy applicable to a small fraction of patients. Thus, new strategies are needed to improve the management of HCC. We evaluate here the efficacy and safety of XON9, a first-in-class glyco-humanized polyclonal antibody (GH-pAb). Cytotoxic activity of XON9 against Hep3B, Huh7, HepG2 or primary hepatocytes was investigated. Apoptosis, caspase activity, production of reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were evaluated. Efficacy of XON9 was then assessed in vivo in NMRI nude mice, while pharmacokinetics and safety were evaluated in a non-human primate. XON9 showed a potent complement-dependent cytotoxicity (CDC) against Hep3B and Huh7 (EC50 < 10 µg/mL), and to a less extent against HepG2. XON9 induced apoptosis of HCC cells with activation of caspases 8 and 9, increase in ROS and drop in MMP. Overall, in vitro lytic activity of XON9 was superior to that of Sorafenib. In vivo, XON9 significantly reduced tumor progression and outperformed Sorafenib. No toxicity was observed after repeated injections of XON9 in a non-human primate. XON9 represents a promising and selective immunotherapy against refractory HCC. Full article

Listeria monocytogenes is a life-threatening bacterial foodborne pathogen that can persist in food-processing facilities for years. Although phages can control L. monocytogenes during food production, phage-resistant bacterial subpopulations can regrow in phage-treated environments. In this study, an L. monocytogenes hly defective strain, NJ05-Δhly, was produced, which considerably regulated the interactions between L. monocytogenes and phages. Specifically, we observed a 76.92-fold decrease in the efficiency of plating of the defective strain following infection with the Listeria phage vB-LmoM-NJ05. The lytic effect was notably diminished at multiplicities of infection of 1 and 10. Furthermore, the inactivation of LLO impaired biofilm formation, which was completely suppressed and eliminated following treatment with 10⁸ PFU/mL of phage. Additionally, phages protected cells from mitochondrial membrane damage and the accumulation of mitochondrial reactive oxygen species induced by L. monocytogenes invasion. Transcriptomic analysis confirmed these findings, revealing the significant downregulation of genes associated with phage sensitivity, pathogenicity, biofilm formation, and motility in L. monocytogenes. These results underscore the vital role of LLO in regulating the pathogenicity, phage susceptibility, and biofilm formation of L. monocytogenes. These observations highlight the important role of virulence factors in phage applications and provide insights into the potential use of phages for developing biosanitizers. Full article

Plant-parasitic nematodes represent a significant threat to agriculture, causing substantial economic losses worldwide. Among the biological alternatives for their control, the genus Trichoderma has emerged as a promising solution for suppressing various nematode species. This article reviews key studies on the interaction between Trichoderma spp. and plant-parasitic nematodes, highlighting the most studied species such as Trichoderma harzianum, Trichoderma longibrachiatum, Trichoderma virens, and Trichoderma viride, mainly against the genera Meloidogyne, Pratylenchus, Globodera, and Heterodera. Trichoderma spp. act through mechanisms such as mycoparasitism, antibiosis, competition for space in the rhizosphere, production of lytic enzymes, and modulation of plant defense responses. They also produce metabolites that affect nematode mobility, reproduction, and survival, such as gliotoxin, viridin and cyclosporine A. In addition, they secrete enzymes such as chitinases, proteases, lipases, and glucanases, which degrade the cuticle of nematodes and their eggs. Furthermore, Trichoderma spp. induce systemic resistance in plants through modulation of phytohormones such as jasmonic acid, ethylene, salicylic acid and auxins. The use of Trichoderma in integrated nematode management enables its application in combination with crop rotation, organic amendments, plant extracts, and resistant varieties, thereby reducing the reliance on synthetic nematicides and promoting more sustainable and climate-resilient agriculture. Full article

Background: Human herpesviruses are double-stranded DNA viruses of which eight types have been identified at present. Herpesvirus infection comprises an active lytic phase and a lifelong latency phase with the possibility of reactivation. These infections are highly prevalent worldwide and can lead to a broad spectrum of clinical manifestations, ranging from mild symptoms to severe disease, particularly in immunocompromised individuals. Clustered regularly interspaced palindromic repeats (CRISPR)-based therapy is an interesting alternative to current antiviral drugs, which fail to cure latent infections and are increasingly challenged by viral resistance. Objective: This scoping review aimed to summarize the current state of CRISPR-based antiviral strategies against herpesvirus infections, highlighting the underlying mechanisms, study design and outcomes, and challenges for clinical implementation. Design: A literature search was conducted in the databases PubMed and Web of Science, using both a general and an individual approach for each herpesvirus. Results: This scoping review identified five main mechanisms of CRISPR-based antiviral therapy against herpesvirus infections in vitro and/or in vivo. First, CRISPR systems can inhibit the active lytic replication cycle upon targeting viral lytic genes or host genes. Second, CRISPR technologies can remove latent viral genomes from infected cells by targeting viral genes essential for latency maintenance or destabilizing the viral genome. Third, reactivation of multiple latent herpesvirus infections can be inhibited by CRISPR-Cas-mediated editing of lytic viral genes, preventing a flare-up of clinical symptoms and reducing the risk of viral transmission. Fourth, CRISPR systems can purposefully induce viral reactivation to enhance recognition by the host immune system or improve the efficacy of existing antiviral therapies. Fifth, CRISPR technology can be applied to develop or enhance the efficiency of cellular immunotherapy. Conclusions: Multiple studies demonstrate the potential of CRISPR-based antiviral strategies to target herpesvirus infections through various mechanisms in vitro and in vivo. However, aspects regarding the delivery and biosafety of CRISPR systems, along with the time window for treatment, require further investigation before broad clinical implementation can be realized. Full article

Background: Multidrug-resistant (MDR) Escherichia coli (E. coli) strains pose a significant public health challenge, which has led to the exploration of alternative therapeutic strategies. Due to their antibacterial and immunomodulatory properties, bacteriophages have emerged as promising therapeutic agents. Methods: This study investigates the effects of GADS24, a novel lytic bacteriophage of E. coli, on human-monocyte-derived dendritic cells (DCs). DCs are exposed to purified GADS24 phage, bacterial lysate, or a combination of both. Flow cytometry was used to assess the expression of surface markers (HLA-DR, CD80, CD83, and CD86), and ELISA was used to measure cytokine production (IL-10 and IL-12p70). Results: Following treatment with bacterial lysate, a significant increase in DC maturation markers was observed. The GADS24 phage alone induced a moderate upregulation of these markers, decreased IL-10 secretion, and increased IL-12p70. Combining bacterial lysate and phage tempered the maturation response compared to the lysate treatment alone. Conclusion: These findings suggest that GADS24 exerts antibacterial activity and modulates host immunity by influencing DC maturation and cytokine production. Due to its dual antimicrobial and immunomodulatory functions, GADS24 is likely to be a valuable adjunctive therapy for multidrug-resistant (MDR) bacterial infections. Furthermore, in vivo studies are necessary to confirm these promising in vitro results. Full article

Enterococcus faecalis (E. faecalis) is a major pathogen responsible for refractory apical periodontitis (RAP). It can penetrate deep into dentinal tubules, form persistent biofilms, and exhibit antibiotic resistance, thereby limiting the efficacy of conventional antimicrobial treatments. Bacteriophages (phages), due to their strong lytic activity and host specificity, have emerged as promising alternatives. In this study, a novel strictly lytic phage, ZXL-01, was isolated from lake water in Jilin, China. ZXL-01 demonstrated remarkable stability under extreme conditions, including thermal tolerance at 60 °C for 1 h and a wide pH range (4–11). Whole-genome sequencing (GenBank accession number: ON113334) revealed a genome of 40,804 bp with no virulence or tRNA genes, confirming its identity as an E. faecalis phage. Importantly, ZXL-01 exhibited potent antibiofilm activity, reducing biofilm biomass by approximately 69.4% in the inhibition group and 68.4% in the lysis group (both p < 0.001). In an in vitro root canal infection model induced by E. faecalis, scanning electron microscope (SEM) observations confirmed that ZXL-01 effectively inhibited biofilm formation and disrupted mature biofilms. These findings highlight the potential of ZXL-01 as a novel antimicrobial agent for the treatment of E. faecalis-associated apical periodontitis. Full article