Search Results (228)

Herpes simplex virus 1 (HSV-1) entry is a complex interplay of viral and host factors. The mechanisms of its regulation remain undefined. HSV-1 entry occurs via multiple distinct and cell-type dependent pathways, further complicating study of this process. HSV-1 strains with atypical entry properties aid in the elucidation of entry determinants. HSV-1 strain ANG path exhibits entry in Vero cells at 4 °C, whereas wild-type strains do not. We investigated the determinants of low temperature entry by HSV-1 ANG path in several cell types. The receptor nectin-2 mediated 4 °C entry of HSV-1 ANG path into CHO-K1 cells, but the related receptor nectin-1 did not, suggesting that gD-binding receptors are a determinant of HSV-1 entry at low temperatures. In HaCaT cells, both HSV-1 ANG path and wild-type strain KOS entered at 4 °C, while HSV-1 chimera 27/III, which contains KOS strain gB in the ANG path virus background, did not. This suggests that gB functions as a determinant of low temperature entry of HSV-1. Together, the findings suggest that there are multiple determinants and mechanisms of HSV-1 low temperature entry and that the requirements differ by cell type. Full article

Herpes simplex virus type 1 (HSV-1) has been proposed as an environmental risk factor for Alzheimer’s disease (AD). Viral infection of neuronal cells can reproduce hallmark pathological features of AD, including intracellular beta-amyloid (Aβ) accumulation, tau hyperphosphorylation, and lysosomal dysfunction. However, the molecular mechanisms underlying these alterations remain unclear, partly due to limitations of existing experimental models. Here, we established both two-dimensional (2D) and three-dimensional (3D) LUHMES neuronal cultures—a human mesencephalic-derived neural cell line that differentiates rapidly into mature neurons—to investigate HSV-1-induced AD-associated markers. Our results demonstrate that HSV-1 infection induces key features of AD, including intracellular accumulation of Aβ peptides and hyperphosphorylation of tau protein. Moreover, we observed disruptions in the autophagy–lysosome pathway, characterized by increased LC3-II levels, reduced cathepsin activity, and impaired lysosomal burden. Notably, these AD-like alterations were reproduced in 3D LUHMES neuronal aggregates, confirming their susceptibility to productive HSV-1 infection. Collectively, these findings indicate that HSV-1 not only triggers AD-like neuropathological markers but also disrupts cellular clearance mechanisms that may contribute to neuronal dysfunction and degeneration. This study validates the 3D LUHMES system as a useful human neuronal model to study virus-induced neurodegeneration and its mechanistic links to AD pathology. Full article

The ongoing emergence of antiviral drug resistance underscores the critical need for new broad-spectrum antiviral agents. Sulfonamides and their derivatives have emerged as promising candidates for the development of new antiviral therapeutics. In this study, a series of camphor-10-sulfonamide derivatives was synthesized through a feasible and sustainable synthetic approach starting from naturally available precursors and evaluated for antiviral properties. Their activity was examined against three structurally distinct viruses—herpes simplex virus type 1 (HSV-1), human coronavirus (HCoV-OC43), and feline calicivirus (FCV)—representing both DNA and RNA, enveloped and non-enveloped types. The compounds were examined for their effects on viral replication, the stage of viral adsorption to the cell, and extracellular virions. The weakest cytotoxicity and the most pronounced activity of all the tested substances was demonstrated by the tryptophan derivative 7a. A time-dependent inhibition of the stage of adsorption of HCoV-OC43 (Δlg = 2.0 at 120 min) and FCV (Δlg = 1.75 at 60 min) to susceptible cells was established, as well as virucidal activity on the three types of virions tested, with the most pronounced effect at 120 min—for HSV-1 (Δlg = 2.75) and Δlg = 2.0 for HCoV-OC43 and FCV. Molecular docking studies performed using Glide (Schrödinger) provided insights into the active conformations of the most effective ligands and predicted possible interactions with relevant viral targets, supporting their potential as lead structures for further therapeutic development. Full article

Zinc oxide nanoparticles (ZnO NPs) have attracted growing interest in several fields, including topical biomedical applications, due to their stability, biocompatibility and therapeutic potential. In this study, chitosan (Ch), gelatin (G) and arabic gum (AG) were combined to formulate hydrogels loaded with different ZnO NP concentrations. The main aim is to assess the synergy between the properties of biopolymers and ZnO moieties in terms of antiviral activity. ZnO NPs were synthesized via co-precipitation. Hydrogels were prepared using the freeze–thaw method, and the loading of 2.5, 5 and 7.5% w/w of ZnO NPs with respect to Ch was promoted by ultrasonication. The structural, morphological, surface and thermal properties of hydrogels loaded with ZnO NPs (HZ 2.5, HZ 5 and HZ 7.5) and the control matrix (H) were characterized using FTIR spectroscopy, confirming the successful incorporation and interaction of ZnO NPs with the polymeric network. Low ZnO NP concentrations enhanced the swelling degree of the hydrogels (from 1044% to 1253%), improving their thermal stability and solubility (96 h vs. 48 h HZ 7.5 and 14 h in the case of H). This behavior could be ascribed to the aggregation of ZnO NPs with increasing amounts, which was verified through FESEM. Virucidal activity was tested against herpes simplex virus type 1 (HSV-1) and bovine coronavirus (BCoV), demonstrating a substantial enhancement when the ZnO NPs are added independently of the concentration. An almost 100% viral inhibition was recorded when the HZs were analyzed, whereas the H matrix showed an inhibition of about 40% against the same virus. Antioxidant activity was evaluated via the DPPH free radical inhibition method, revealing an improvement with the loading of NPs. Full article

Background/Objectives: Polymerase chain reaction (PCR) testing of ocular fluids is an essential diagnostic method for identifying infectious causes of uveitis. However, multiplex PCR kits specifically developed for ophthalmic use are not commercially available in many regions, including Korea. Given the biochemical similarity between cerebrospinal fluid (CSF) and aqueous humor, this study evaluated the diagnostic utility of a commercially available CSF multiplex PCR panel for detecting herpesviruses in patients with suspected viral uveitis. Methods: We retrospectively reviewed the medical records of patients whose aqueous humor samples were analyzed using a multiplex PCR assay originally designed for CSF testing (Seeplex Meningitis-V1 ACE Detection kit, Seegene, Seoul, Republic of Korea). The samples were obtained between May 2019 and June 2023 at two tertiary referral hospitals. The assay targeted herpes simplex virus types 1 and 2 (HSV-1, HSV-2), varicella-zoster virus (VZV), cytomegalovirus (CMV), Epstein–Barr virus (EBV), and human herpesvirus 6 (HHV-6). Patients were classified into three groups: (I) anterior uveitis with suspected herpesviral infection, (II) acute retinal necrosis (ARN), and (III) CMV retinitis. Baseline characteristics, PCR positivity rates, and virus prevalence were compared among the groups. Results: Among 149 eyes tested, 86 were included in the final analysis. The overall positivity rate was 38.4%. PCR positivity was 19.7% (12/61) in Group I, 93.8% (15/16) in Group II, and 66.7% (6/9) in Group III. CMV was the most common pathogen in Groups I (66.7%) and III (100%), while VZV was predominant in Group II (80%). No HHV-6 infection was detected. Conclusions: The positivity rate in anterior uveitis (Group I) was lower than previously reported, likely due to the limited sample volume relative to the assay’s requirement. Nevertheless, the assay demonstrated diagnostic reliability comparable to previous reports for ARN and CMV retinitis. Therefore, the CSF-based multiplex PCR panel serves as a feasible and cost-effective diagnostic option for sight-threatening posterior segment infections, facilitating prompt diagnosis and treatment, although further optimization is warranted for anterior uveitis. Full article

Many studies have shown an association between herpes simplex virus type 1 (HSV-1) infection and the development of neurodegeneration processes later in life, such as Alzheimer’s disease. The Fas/FasL death pathway plays an important role in the complex regulation of the local inflammatory response and mounting of the specific antiviral response in HSV-1 infection. Here, we applied a mouse model of latent HSV-1 neuroinfection to Fas- and FasL-deficient mice (lpr and gld) to explore whether the lack of functional Fas/FasL pathway protects from inflammation-related neurodegeneration. The latently infected Fas- and FasL-deficient mice (lpr and gld) were not protected from virus replication despite the accumulation of virus-specific cytotoxic T cells. However, the lack of Fas/FasL pathway decreased neuroinflammation- and neurodegeneration-related markers, including cognitive impairment, amyloid-β protein, and tau hyperphosphorylation. The use of a glucocorticoid, dexamethasone, to decrease neuroinflammation in wild-type mice did not protect from cognitive impairment, despite the improved antiviral response. Our data indicate that excessive neuroinflammation via the Fas/FasL pathway during HSV-1 infection is associated with neurodegeneration. Furthermore, the administration of immunomodulatory agents to ameliorate the outcome of HSV-1 latent infection should be restricted to the peak of neuroinflammation. Full article

Mutations in the NF1 gene cause Neurofibromatosis Type 1 (NF1), one of the most common genetic disorders. This gene encodes neurofibromin, a member of the GTPase-activating protein (GAP) family that functions as a negative regulator of RAS signaling. Loss of NF1 function leads to persistent RAS activation and promotes tumor growth. The clinical manifestations of NF1 mainly include pigmentary changes, benign and malignant peripheral nerve sheath tumors, as well as gliomas affecting the central nervous system. Currently, MEK inhibition is the only approved therapy and is primarily effective in controlling plexiform neurofibromas (pNFs). However, more comprehensive treatments are needed to address the full spectrum of NF1 manifestations and malignant transformation. Novel therapeutic strategies, including AAV-based gene therapy aimed at restoring NF1 function, oncolytic herpes simplex virus (oHSV) therapy targeting RAS-dysregulated tumor cells, and chimeric antigen receptor T cell (CAR-T) therapy targeting NF1-associated tumors, are under active investigation. In this review, we explore the genetic mechanisms underlying NF1 and highlight recent advances in therapeutic development with a special focus on AAV-based gene therapies alongside other approaches with recent clinical and translational advancements. Full article

This study investigated the in vitro and in silico anticancer and antiviral potential of three Lamiaceae essential oils (EOs), Rosmarinus officinalis (REO), Salvia officinalis (SEO), and Mentha × piperita (MEO). The essays included both Eos tested individually and in combination. Cytotoxicity was assessed in normal dermal fibroblast (NHDF), breast (MCF7), lung (A549), and colorectal (LoVo) cell lines. Antiviral activity was evaluated against herpes simplex virus type 1 (HSV-1) and adenovirus type-5 (AdV-5). Major identified compounds were subjected to in silico analysis against selected cancer- and virus-related protein targets. None of the EOs or their combinations showed cytotoxicity toward NHDF cells. REO exhibited significant anticancer activity against MCF7 and A549 cells, while SEO displayed the greatest antiproliferative effect on MCF7 cells. MEO showed moderate activity against MCF7 cells and weak activity against A549 cells. All EOs and combinations showed limited efficacy against LoVo cells. Combined EOs were more effective against A549 cells, showing synergism for REO combinations, whereas lower activity was noted against MCF7 cells, where the MEO + SEO combination exhibited an antagonistic effect. All EOs and their combinations effectively reduced HSV-1 and AdV-5 titers. In silico results confirmed the binding affinities between the major EO compounds and selected protein targets, supporting their potential as complementary therapeutic agents. Full article

The emergence of multidrug-resistant microbes presents a serious public health threat that requires new antimicrobial methods. A potential solution to combat resistance involves using metal nanoparticles that possess improved biological characteristics. The researchers have synthesized gold nanoparticles (Au-NPs) using gamma irradiation of Polyacrylamide (PAM) at 5, 10, and 15 kGy doses and through Au/chitosan nanocomposite production methods. They have also assessed the antimicrobial and anticancer functions of the produced nanomaterials by testing them on various microorganisms and cancer cell lines. Gold nanoparticles exhibited strong antibacterial effects against multiple Gram-positive bacterial strains, including Bacillus subtilis, Micrococcus luteus, Staphylococcus epidermidis, Staphylococcus aureus, and Streptococcus mutans, as well as methicillin-resistant Staphylococcus aureus (MRSA). Escherichia coli showed a significant inhibition zone of 23 mm, and Salmonella spp. showed similar inhibition. The inhibition zone for Klebsiella pneumoniae ATCC 13883 revealed resistance. The Au-NPs/chitosan composite showed moderate antifungal effectiveness against Syncephalis racemosum and Aspergillus niger alongside Candida albicans and several other tested fungi. Au-NPs showed cytotoxicity to breast MCF-7 cells, as well as liver HepG-2 cells and colon HCT-116 cells. The combination of Au-NPs with chitosan demonstrated limited effectiveness in countering hepatitis A virus (HAV-10) and herpes simplex virus type 1 (HSV-1). The combination of gamma-irradiated Au-NPs with biopolymers like chitosan demonstrates significant promise in antimicrobial and anticancer biomedical applications. Full article

Oncolytic viruses represent an emerging class of therapeutic agents that have the potential to transform the care of patients with melanoma. In this narrative review, we describe the evolution of oncolytic virus approaches. We begin by describing early investigations using wild type viruses and then the development of sophisticated Herpes simplex virus 1 (HSV-1) variant constructs such as talimogene laherparepvec (T-VEC) and vusolimogene oderparepvec (Replimune-1, RP1), which incorporate deletions of viral genes and expression of human or synthetic transgenes to promote tumor selectivity, dendritic cell recruitment, antigen presentation, and stimulation of systemic anti-tumor immune responses. We review the status of clinical trials of oncolytic viruses in melanoma, highlight regulatory challenges, and describe important concepts and key remaining questions within the field. While T-VEC remains the only Food and Drug Administration (FDA)-approved oncolytic virus for melanoma treatment, ongoing research focusing on next-generation viral constructs and combination strategies aims to further improve clinical outcomes and expand the applicability of oncolytic virus therapy in melanoma. Full article

Herpes simplex virus type 1 (HSV-1) is a leading cause of infectious corneal blindness worldwide. Human donor corneal transplantation remains the primary treatment for scarred corneas resulting from herpes simplex keratitis (HSK), a severe inflammatory corneal disease caused by HSV-1 infection, despite a high risk of re-infection or immune rejection of the allografts. As possible alternatives to donor grafting for HSK, we developed cell-free, regeneration-stimulating corneal implants designed to work even under adverse inflammatory situations such as severe infections. The implants comprised short, fully synthetic collagen-like peptides conjugated to polyethylene glycol (CLP-PEG) and crosslinked using carbodiimide chemistry. Being cell-free, they lacked the cellular targets that an already activated immune system would encounter in these inflamed corneas. We tested the performance of these implants in guinea pig and rabbit models of HSK. Three different HSV-1 strains were used to create experimental HSK in rabbits and guinea pigs. There were no overall statistically significant species differences or species–strain differences in virus-induced mortality. At three months post-operation, all treated corneas showed tissue regeneration, but with haze or neovascularization. The initially cell-free CLP-PEG implants allowed for repopulation by ingrowing cells to regenerate neocorneal tissue, despite the inflammation. However, they did not prevent HSV-1 reactivation nor re-infection, as neovascularization and disorganization were observed within the neocorneas. A detailed histopathological examination revealed viral strain differences, but only KOS infection showed interspecies neovascularization differences. A more detailed examination with larger numbers of animals is merited to fully elucidate the effects of the different viral strains on rabbits versus guinea pigs. Full article

Herpes simplex virus type 1 (HSV-1) is a continuous health challenge, and current antiviral treatments cannot cure the virus. As life expectancy continues to increase worldwide, HSV-1 should remain a focus to minimize its associated health complications within the aging population. While often asymptomatic, HSV-1 causes oral and cutaneous lesions and establishes latency with periodic reactivation. Antivirals reduce symptoms but do not eradicate the virus. Emerging evidence links HSV-1 to Alzheimer’s disease (AD) via chronic neuroinflammation, amyloid-beta and tau accumulation, oxidative stress, and synaptic dysfunction, with viral proteins detected in AD-affected brain regions. This review assesses the current evidence for HSV-1 in dementia pathogenesis, examines antiviral strategies as potential neuroprotective interventions, and outlines the experimental models required to establish causality. Full article

Background: Encapsulating essential oils in polymer-based nanocarriers can improve their stability, solubility, and bioavailability, while maintaining the biological activity of the oil’s active ingredients. In this contribution, we investigated the antiviral activity of Oregano Essential Oil (OEO) in its pure form and encapsulated into nanosized polymeric micelles, based on a poly(ethylene oxide)-block-poly(ε-caprolactone) diblock copolymer. Methods: The effect of encapsulation was evaluated using three structurally different viruses: herpes simplex virus type 1 (HSV-1) (DNA—enveloped virus), human coronavirus (HCoV OC-43) (RNA—enveloped virus), and feline calicivirus (FCV) (RNA—naked virus). The effect on the viral replicative cycle was determined using the cytopathic effect inhibition (CPE) test. Inhibition of the viral adsorption step, virucidal activity, and protective effect on healthy cells were assessed using the final dilution method and were determined as Δlg compared to the untreated viral control. Results: In both studied forms (pure and nanoformulated), OEO had no significant effect on viral replication. In the remaining antiviral experiments, the oil embedded into nanocarriers showed a slightly stronger effect than the pure oil. When the oil was directly applied to extracellular virions, viral titers were significantly reduced for all three viruses, with the effect being strongest for HSV-1 and FCV (Δlg = 3.5). A distinct effect was also observed on the viral adsorption stage, with the effect being most significant for HSV-1 (Δlg = 3.0). Conclusions: Pretreatment of healthy cells with the nanoformulated OEO significantly protected them from viral infection, with the greatest reduction in viral titer for HCoV OC-43. Full article

Background/Objectives: The skin is a protective barrier against pathogens such as herpes simplex virus type 1 (HSV-1), which causes recurrent and highly prevalent skin infections worldwide. The increasing resistance of HSV-1 to conventional treatments has driven the search for new therapeutic alternatives. In this context, the essential oil of Lippia graveolens (EOL) has demonstrated promising antiviral activity; however, its high volatility limits direct skin application. To overcome this, polymeric nanoparticles (NPs) loaded with EOL were developed to improve its availability and antiviral efficacy. Methods: Nanoformulations were prepared by nanoprecipitation, and their antiviral activity against HSV-1 was evaluated using the plaque reduction assay. The effect of the nanoformulations on skin barrier integrity was assessed using an ex vivo porcine skin model and non-invasive techniques. Results: The NP-EOL exhibited physicochemical properties favorable for skin deposition, including a particle size around 200 nm, a polydispersity index of ≤ 0.2, and negative zeta potential. Moreover, NP-EOL showed 1.85-fold higher antiviral activity against HSV-1 compared with free EOL, while also reducing cytotoxicity in Vero cells. Conclusions: Results demonstrated that the NPs promoted skin hydration without altering pH or transepidermal water loss, suggesting they do not disrupt skin homeostasis. This study supports the potential of NP-based systems as effective topical delivery vehicles for EOL, representing a promising therapeutic alternative against HSV-1 skin infections. Full article

Background/Objectives: Schizophrenia (SCH), bipolar disorder (BPD), and major depressive disorder (MDD) are increasingly viewed as neuroimmune disorders shaped by viral exposure and inflammation. Disorder-specific immunovirological profiles, however, remain poorly defined. Methods: In this cross-sectional study, we assessed Epstein–Barr Virus (EBV) and Herpes Simplex Virus type 1 (HSV-1) seropositivity and measured serum CRP, IL-6, and IL-1β in 708 participants: 110 with SCH, 121 with BPD, 135 with MDD, and 342 healthy controls (HC). Statistical analyses included Shapiro–Wilk tests for normality; Kruskal–Wallis with Bonferroni-adjusted Dunn post hoc comparisons; and logistic regression adjusted for age, sex, and marital status. Results: EBV seropositivity was higher in SCH (90.9%) than in HC (78.9%) (OR = 3.46, 95% CI: 1.68–7.12; p = 0.001) but not in BPD or MDD. HSV-1 seropositivity was elevated in BPD (83.5%) versus HC (67.0%) (OR = 2.29, 95% CI: 1.34–3.92; p = 0.003), with no differences in SCH or MDD. Inflammatory biomarkers were significantly increased in SCH and MDD compared to HC (p < 0.001), while BPD showed no differences. Conclusions: The findings delineate distinct immunovirological patterns across major psychiatric disorders. Schizophrenia was characterized by EBV seropositivity accompanied by systemic inflammatory activation, bipolar disorder by HSV-1 seropositivity in the absence of inflammatory changes, and major depressive disorder by inflammatory dysregulation independent of viral exposure. These disorder-specific profiles highlight heterogeneity in neuroimmune pathways and underscore the potential relevance of biomarker-based stratification for generating hypotheses regarding targeted antiviral or anti-inflammatory interventions in psychiatric populations. Full article