Search Results (697)

Oncolytic viruses represent a promising class of anticancer therapeutics, and rapid, accurate quantification of viral titers is critical for ensuring both efficacy and safety during clinical development. Conventional viral titering methods, such as 50% cell culture infectious dose (CCID₅₀), are time-consuming and limited in sensitivity, thereby restricting their application in real-time clinical monitoring. This study aimed to develop and validate a rapid titer assay for oHSV2-PD-L1/CD3-BsAb, an oncolytic herpes simplex virus expressing a PD-L1/CD3 bispecific antibody, to support preclinical and clinical monitoring. A dual-reporter cell system was established using Vero-PD-L1-GFP (Vero cells expressing PD-L1 and GFP) cells as target cells and Jurkat-NFAT-Fluc (Jurkat cells expressing NFAT and Fluc) cells as effector cells. Viral infection activates the NFAT signaling pathway, driving Fluc expression, thereby enabling rapid quantification of infectious virus. The assay was evaluated for specificity, limit of detection (LOD), and lower limit of quantification (LLOQ), and compared with the conventional CCID₅₀ method. Its applicability was further assessed using clinical simulation samples, including PBMCs and swabs. The rapid titer assay accurately quantified virus at 10³ CCID₅₀/mL after 8 h of incubation, consistent with CCID₅₀ results, while extending the incubation to 18 h improved the LLOQ to 10^2.5 CCID₅₀/mL, demonstrating enhanced sensitivity. The assay exhibited high reproducibility and stability in both PBMC and swab samples, enabling reliable quantification of low-titer virus in complex biological matrices. Compared with CCID₅₀, the method substantially reduced assay time (from 3–5 days to 8–18 h) while improving sensitivity and specificity. The developed rapid titer assay for oHSV2-PD-L1/CD3-BsAb provides a sensitive and specific platform for viral quantification. It offers a valuable tool for oncolytic virus development, production quality control, and clinical monitoring, facilitating efficient safety evaluation and risk management in ongoing and future clinical applications. Full article

HP1090 is a short, cationic, amphipathic peptide derived from scorpion venom and previously described as a membrane-active antiviral compound. Here, we primarily characterize the antiviral activity of HP1090 and assess whether additional antibacterial effects are consistent with membrane-disruptive properties. Chemically synthesized HP1090 exhibited dose-dependent virucidal activity against multiple enveloped viruses, including herpes simplex virus type 1 and 2 (HSV-1, HSV-2), human immunodeficiency virus type 1 (HIV-1), and Zika virus (ZIKV), with IC₅₀ values ranging from 14.7 to 56.1 µg/mL. No activity was observed against the non-enveloped human rhinovirus 14 (HRV14), suggesting strict dependence on a viral lipid envelope. Consistent with a membrane-targeting mechanism, HP1090 induced rapid and concentration-dependent permeabilization of virus-like liposomes. HP1090 also displayed antibacterial activity against selected clinically relevant pathogens in agar-based growth inhibition assays. However, antibacterial effects required substantially higher concentrations (>125 µg/mL) and varied between bacterial species, with some strains showing little or no susceptibility. Membrane permeabilization assays in Listeria monocytogenes demonstrated disruption of bacterial membrane integrity as a contributing mechanism. No cytotoxicity was observed on mammalian cell lines at effective antiviral concentrations. Together, these findings establish HP1090 as a membrane-active venom peptide and, by linking envelope-dependent viral inactivation with bacterial membrane permeabilization, support a shared biophysical mode of action relevant to the development of membrane-targeting anti-infectives. Full article

Herpes simplex virus type 1 (HSV-1) remains a significant pathogen, particularly in immunocompromised patients. The emergence of drug-resistant strains necessitates alternative therapeutic agents. Lentinula edodes (LE), Hypsizygus marmoreus, and Pleurotus eryngii are edible mushrooms with recognized medicinal properties. However, their effects on drug-resistant HSV-1 remain unclear. This study characterized metabolites from high-temperature/high-pressure (121 °C) water extracts of fresh and dried fruiting bodies and evaluated anti-HSV-1 activities using in vitro and in silico approaches. Metabolic profiles were analyzed by electrospray ionization–quadrupole time-of-flight mass spectrometry. Antiviral activity against HSV-1 KOS (wild-type) and HSV-1 dxpiii (drug-resistant) strains was assessed by plaque assays and qPCR. Molecular docking and network pharmacology were performed on candidate compounds. LE extract from dried mushroom tended to show the highest levels of selected major bioactive constituents, along with greater antioxidant activities. All extracts significantly inhibited viral infection and gene expression in both strains. LE extract from dried mushroom modulated the expression of NFKB1 and IL6. Molecular docking analysis revealed that eritanidine showed a predicted binding affinity to HSV-1 DNA polymerase (−7.95 kcal/mol). Additionally, eritanidine, 5′-methylthioadenosine, and 3-indoleacrylic acid were predicted to interact with TNF and MAPK1. Several compounds also demonstrated favorable drug-likeness properties. Overall, these mushroom extracts are promising natural sources of antiviral agents against HSV-1, including drug-resistant variants. Full article

Herpesvirus infections belong to major pathogens in the human population. This study aimed at evaluating diagnostic data for eight human herpesviruses, based on datasets derived from a large European tertiary care center. Specifically, we analyzed 118,692 herpesvirus submittals to the Diagnostic Division of the Virological Institute, University Hospital Erlangen (UKER), Germany, between July 2014 and June 2024. Our points of focus were the following: (i) the frequencies of herpesvirus diagnostic results with positivity rates, (ii) departments representing main sample submitters, (iii) the specific importance of intensive care units (ICUs), (iv) the COVID-19 pandemic period, and (v) distinct properties of sample types. Overall, we are stating the highest frequencies of diagnostic assessment for herpes simplex virus (HSV), human cytomegalovirus (HCMV), and Epstein–Barr virus (EBV) infections, pointing to their dominant relevance for clinical practice. Notably, HCMV submittals (46.6% of total), together with EBV (26.2%) and HSV (15.7), accounted for almost 90% of all herpesviral diagnostic samples during this period. Within these key groups, HCMV, EBV and HSV showed positivity rates of 14.5%, 35.0%, and 18.5%, respectively. Concerning a main input of sample submittals, two departments were predominant in our center, i.e., the Departments of Haematology–Oncology and Anaesthesiology. These included patients under multifold types of treatment associated with an increased risk of herpesvirus reactivation or primary infection. Furthermore, another high portion of submittals was noted for ICUs and external sources. In addition, a numerical, transient increase in herpesvirus diagnostic submittals, from various sources, was shown for the COVID-19 pandemic years (mostly 2021) as compared to other periods. Combined, these data underlined the importance of clinical monitoring of herpesvirus infections, particularly for high-risk patients, and the steady need of improvements in preventive measures, therapeutic options, and safe diagnostic tools. Full article

Background/Objectives: This study aimed to investigate the genital pathogen profile and co-infection dynamics using multiplex RT-qPCR, specifically evaluating the independent associations with age, sex, and HIV status. Methods: Data from 1217 patients who underwent a sexually transmitted infection (STI) panel study at the Microbiology Laboratory of Marmara University Pendik Training and Research Hospital between January 2024 and December 2025 were retrospectively reviewed. Pathogen detection was performed using a commercial kit (Bioeksen, Istanbul, Türkiye) with the multiplex RT-qPCR method. The independent effects of HIV positivity, age, and sex on pathogen frequency and co-infection were analyzed using logistic regression models; results were evaluated using adjusted odds ratio (aOR) and 95% confidence interval (CI). Results: Any-pathogen positivity was detected in 57.8% of patients, with Ureaplasma spp. (36.9%) and Gardnerella vaginalis (32.5%) being the most prevalent. While overall pathogen positivity did not differ significantly by HIV status (p = 0.158), HIV-positive patients exhibited distinct microbiological architectures. Higher positivity rates were observed in women in both groups, and a strong correlation was found between sex and the presence of infection (p < 0.001). Multivariate analysis revealed that HIV positivity was independently associated with an over fivefold increase in HSV-2 detection (aOR = 5.09, 95% CI: 1.47–17.65; p = 0.010). Furthermore, HIV-positive individuals were significantly enriched for complex polymicrobial patterns involving three or more pathogens (p = 0.008). Conversely, male sex was independently associated with a substantially lower risk of co-infection (aOR = 0.17, 95% CI: 0.12–0.22; p < 0.001), and increasing age showed an inverse relationship with co-infection frequency (aOR = 0.98 per year, 95% CI: 0.97–0.99; p = 0.001). Conclusions: This study adds to current epidemiological evidence by showing that genital pathogen distribution is shaped by age- and sex-related heterogeneity, with flora-associated co-infections predominating in women and more classical STI-related agents occurring more often in men. Our findings suggest that multiplex RT-qPCR provides value not only for broad pathogen detection but also for identifying demographic- and HIV-associated co-infection patterns that may support stratified screening and targeted clinical management. Full article

Programmed cell death (PCD) pathways of innate immunity serve to protect host cells from invading viruses. Parthanatos is a novel form of PCD triggered by excessive host cell DNA damage that leads to overactivation of poly(ADP-ribose) polymerase-1 (PARP-1) which in turn stimulates poly(ADP-ribose) (PAR) polymer formation. PAR translocates to the cytoplasm, where it induces release of apoptosis-inducing factor (AIF) from mitochondria, that then travels back to the nucleus, where it mediates large-scale DNA fragmentation and cell death. Little information is available regarding parthanatos as a cell death mechanism to dampen herpesvirus replication at the host cell level. A series of studies were therefore performed to clarify a possible role for parthanatos during productive replication of murine cytomegalovirus (MCMV) and herpes simplex virus type 1 (HSV-1) in diverse cell types. These included mouse embryo fibroblasts, mouse lung fibroblasts, mouse microglial (BV-2) cells, and human retinal pigment epithelial (ARPE-19) cells. We report that PAR protein production is surprisingly cell type specific. Moreover, MCMV or HSV-1 infection may suppress parthanatos as observed for other PCD pathways, such as apoptosis, necroptosis, and pyroptosis, in a dose-dependent and cell type-specific manner. We conclude that the operation of parthanatos at the host cell level during herpesvirus replication is more complex than originally thought but offers new targets for possible therapeutic interventions. Full article

The role of human leukocyte antigen F (HLA-F) at the maternal–fetal interface (MFI) during viral infection and its regulation by interferon signaling remains poorly understood. Here, we investigated HLA-F expression and regulation in first-trimester trophoblast cells following activation of the type I interferon pathway and viral infection. We demonstrate that HLA-F is significantly upregulated at both mRNA and protein levels in response to Poly(I:C) and IFN-β in a dose- and time-dependent manner, suggesting its regulation as an interferon-stimulated gene (ISG). Zika virus (ZIKV) infection similarly induced HLA-F upregulation over time. In contrast, HSV-2 infection downregulated HLA-F mRNA while maintaining steady protein levels, indicative of virus-specific regulatory mechanisms. Moreover, we identified a soluble form of HLA-F secreted following Poly(I:C) stimulation. These findings reveal that HLA-F is dynamically regulated in trophoblasts during viral challenge and type I IFN signaling activation, supporting its broader immunomodulatory role in antiviral defense and immune tolerance at the MFI. Full article

Paraspeckles are subnuclear ribonucleoprotein condensates that regulate host stress responses, including those triggered by viral infection. In vitro studies using non-neuronal cells have shown the involvement of specific paraspeckle components in facilitating the replication of certain viruses, including Herpes Simplex Virus 1 (HSV-1), but these processes have not been investigated in human neuronal cells, which represent a relevant target of the virus. We employed human neural precursor cells (NPCs), neurons, and brain organoids derived from hiPSCs to investigate the previously unexplored dynamics of paraspeckle components in HSV-1-infected human neuronal cells. Our results reveal cell-type-specific differences in the expression of paraspeckle genes in response to HSV-1 infection. Unlike other viruses, HSV-1 orchestrates a previously unreported redistribution of paraspeckle proteins, leading to their accumulation in viral replication compartments (VRCs). Importantly, the expression of the paraspeckle proteins NONO and SFPQ correlates with HSV-1 permissiveness in human neuronal cells and may be required to establish a nuclear environment favoring viral transcription/replication. This enhances our understanding of how stress-response pathways in cells can be exploited by viruses in a cell-type-specific manner. Full article

Glioblastoma (GBM) is characterized by a profoundly immunosuppressive tumor microenvironment that limits the efficacy of conventional and immune-based therapies. Oncolytic herpes simplex virus (oHSV) therapy has emerged as a strategy capable of both tumor-selective infection and immune microenvironment modulation. This systematic review aimed to synthesize current evidence on how oHSV therapy reshapes the immunosuppressive microenvironment of GBM. A systematic search of PubMed (MEDLINE) and Embase identified original studies published between 2016 and 2025 investigating immunological or microenvironmental effects of oHSV-based therapies in GBM (final search: 28 January 2026). Preclinical and clinical studies were included, whereas reviews, editorials, conference abstracts, and studies of non-herpes oncolytic viruses were excluded. Study selection and data extraction were performed independently by two reviewers. Due to heterogeneity in models, viral constructs, and outcome measures, a qualitative narrative synthesis was conducted. Of 214 records, 22 studies met the inclusion criteria. Most were preclinical studies using orthotopic immunocompetent murine models, with limited clinical evidence including an early-phase trial in recurrent high-grade glioma. Therapeutic efficacy frequently correlated with tumor microenvironment remodeling rather than viral replication alone. oHSV infection promoted inflammatory signaling, antigen presentation, macrophage polarization, and effector T-cell recruitment but also induced counter-regulatory mechanisms such as myeloid-mediated immunosuppression and vascular or stromal barriers. The clinical significance and durability of these effects remain to be established in larger prospective studies. Despite heterogeneous designs and limited clinical data, current evidence suggests that oHSV may function as a platform for immune microenvironment reprogramming in glioblastoma. Full article

Following acute infection, herpes simplex virus type 1 (HSV-1) establishes life-long latency in neurons. Although sensory neurons in trigeminal ganglia (TG) are primary sites for latency, the brainstem is also an important site for latency. The rationale for examining the principal sensory nucleus of the spinal trigeminal tract (Pr5) receives afferent inputs from TG. Notably, the (LC) is indirectly linked to Pr5. Our previous studies revealed that senescent cells and inflammation were detected in the Pr5 and LC of aged mice and young mice that are latently infected with HSV-1. To expand our understanding of how HSV-1 influences senescence and inflammation in Pr5 and LC, NanoString studies in mice latently infected with wild-type HSV-1 or a latency-associated transcript (LAT) null mutant (dLAT2903) was compared to age-matched uninfected C57Bl/6 male and female mice. LAT is the only viral gene abundantly expressed during latency, suggesting it influences cellular gene expression during latency. Cellular genes that regulate neuron differentiation, axonal projection, and pro-inflammatory mediators were more prevalent in mice latently infected with wild-type (wt) HSV-1 and dLAT2903 versus uninfected mice. Finally, these studies revealed that latency in Pr5 and LC is a dynamic process. Full article

In recent years, nanotechnology has made remarkable progress in the fight against infectious diseases. However, the development of safe and effective antiviral drugs remains a challenge, as viruses rely on host cells for replication. Plant-derived, environmentally friendly nanoparticles have gained significant attention due to their low toxicity, which enables them to target viruses without damaging host cells. In this study, we describe the synthesis of silver nanoparticles (AgNPs) using Arctostaphylos uva-ursi leaf extract and explore their potential antiviral activity. The uva-ursi AgNPs were initially characterized using nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM). We then optimized two different gellan gum/alginate film formulations (1.6:0.4 and 1.2:0.8) as delivery matrices for the AgNPs and assessed Ag⁺ skin permeation using a Franz diffusion cell system. The antiviral potential of the uva-ursi AgNPs—both alone and incorporated into the films—was tested against herpes simplex virus type 1 (HSV-1). Our findings indicate that uva-ursi AgNPs may directly interact with the viral envelope, disrupting the lipid membrane and/or interfering with viral surface proteins. Overall, green-synthesized uva-ursi AgNPs may represent a natural, cost-effective, and safe alternative strategy for managing herpetic infections. Full article

Honey and propolis from the stingless bees Tetragonula drescheri and Tetragonula pagdeni remain underexplored for their health-promoting application. This study investigated the bioactive compounds, and antiviral and anticancer activities of honey and propolis extracts against herpes simplex virus (HSV), and human papillomavirus (HPV-16/18)-positive cervical cancer cells. Water and ethanol extracts were prepared and evaluated for anti-HSV activity using plaque assay, and for anticancer effects on CaSki and HeLa cells using apoptosis, colony formation, cell migration, and candidate gene expression analysis. Propolis water extract most potentially inhibited HSV wild-type and drug-resistant strains. Propolis ethanol extract from T. drescheri markedly suppressed CaSki and HeLa cell growth, induced apoptosis, downregulated HPV-16/18 E6, and upregulated BAX expression. Chemical profiles were identified by electrospray ionization quadrupole time-of-flight mass spectrometry. Most candidate compounds displayed preferable drug-likeness properties. Prototype herbal soup formulations containing selected extracts significantly inhibited HSV-1 drug-resistant strain and HPV-16 E6 expression. These findings demonstrated the high antiviral and anticancer potential of the extracted compounds from T. drescheri and T. pagdeni propolis, supporting their application in health-promoting products against HSV and HPV infection. Full article

A 34-year-old healthy man was referred for colonoscopy due to tenesmus and rectal bleeding in the absence of systemic or immunosuppressive conditions. Incomplete bowel preparation limited the examination, but rectal inspection revealed a well-demarcated erythematous lesion with a granular, micronodular surface and fibrinous areas. The mucosa appeared friable and bled with minimal contact. The differential diagnosis included infectious and inflammatory etiologies. Histologic analysis showed granulation tissue with moderate lymphoplasmacytic infiltration, and C-reactive protein (CRP) confirmed Herpes Simplex Virus type 2 (HSV-2). This case underscores the importance of considering sexually transmitted infections (STIs) such as HSV in the differential diagnosis of rectal bleeding, even in immunocompetent individuals. Full article

Background: Hepatitis B virus (HBV) infection continues to be a major public health concern, especially in sub-Saharan Africa, where widespread epidemics and restricted availability of long-term antiviral therapies result in higher mortality and morbidity rates. Drug repurposing represents a strategic approach to accelerate the discovery of effective therapies by leveraging agents with demonstrated antiviral and immunomodulatory activity. Product Nkabinde (PN) is a patented African polyherbal formulation initially developed for the treatment of HIV. Recent experimental studies demonstrate PN’s potent anti-HIV activity and significant immunomodulatory effects in human immune cells, implicating host-directed mechanisms relevant to chronic viral infections. This study combines an integrative application of network pharmacology and molecular docking to evaluate the repurposing potential of PN as a multi-target agent in HBV. Method: Bioactive components of PN were screened, and compound-associated targets were intersected with HBV-associated genes (proteins) to construct a protein–protein interaction (PPI) network. Topological analysis identified 10 hub targets (STAT1, STAT3, SRC, HCK, EGFR, SYK, PIK3CA, PIK3CB, PIK3R1, and PTPN11). Gene Ontology and KEGG pathway enrichment were performed with an FDR cut-off < 0.05. Significantly enriched pathways included JAK–STAT signaling, chemokine signaling, EGFR-TKI resistance, PI3K complex signaling, and viral infection pathways, particularly those related to Kaposi sarcoma virus and HSV-1, indicating immunoregulatory and antiviral roles. Molecular docking was performed using AutoDock Vina 1.1.2 to evaluate binding affinity and interaction mode of key PN phytochemicals against the hub proteins, and results were compared to their respective co-crystallized ligands. Results: Molecular docking indicated that major phytochemicals from PN exhibited significant binding affinities across all 10 hub host targets, typically outperforming or closely matching their respective co-crystallized ligands. The strongest contacts were observed for β-sitosterol–PIK3CB (−14.2 kcal/mol) and oleanolic acid–SYK (−14.0 kcal/mol), which were significantly stronger than the co-crystallized ligands (−7.9 and −8.3 kcal/mol, respectively), indicating robust stabilization within catalytic and regulatory pockets. Procyanidin B2 toward HCK (−10.5 vs. −7.9 kcal/mol) and PIK3CA (−9.5 vs. −7.3 kcal/mol), quercetin toward PIK3R1 (−10.6 vs. −8.2 kcal/mol) and PTPN11 (−9.2 vs. −7.5 kcal/mol), rutin toward SRC (−10.5 vs. 7.8 kcal/mol), and diosgenin toward EGFR (−9.4 vs. 8.4 kcal/mol). Procyanidin B2 maintained robust multi-hydrogen bonding networks, demonstrating significant binding, despite STAT1 and STAT3 docking showing identical affinities to co-crystals. Conserved hydrogen bonds, π–cation interactions, and significant hydrophobic packing at ATP-binding clefts and regulatory domains supported these interaction patterns, indicating competitive suppression of host signaling nodes taken over by HBV. Conclusions: Together, these results demonstrate that the components of PN possess strong multitarget binding capabilities across the PI3K/AKT, JAK–STAT, SRC-family kinase, EGFR, and SYK pathways, supporting their potential repurposing as host-directed HBV therapeutics with the ability to impede immune evasion, viral persistence, and HBV-associated oncogenic progression. Full article