Search Results (546)

Background: Breast cancer is a complex, multifactorial malignancy characterized by the uncontrolled proliferation of epithelial cells, with certain subtypes exhibiting resistance to conventional therapies. Plant-derived essential oils have been proposed as potential anticancer agents due to their bioactive compounds. Recent studies have demonstrated that Decatropis bicolor essential oil exhibits activity against breast cancer, attributed to diverse secondary metabolites such as δ-cadinene. Aberrant expression of adhesion and invasion proteins, including MMPs, CD44, N-cadherin, and ZEB-2, are key signs of breast cancer progression and metastasis; they represent relevant molecular targets. Objectives: To investigate the interaction of δ-cadinene with these proteins using in silico approaches and in vitro evaluations. Methods: In silico analyses were conducted to assess the interaction and stability of δ-cadinene with target proteins. In vitro assays, including cytotoxicity, morphological analysis, and cell invasion assays, were performed using MDA-MB-231 and MCF10-A cell lines. Results: Interaction analysis suggest that δ-cadinene interacts with key catalytic residues in MMP-2, sharing features with Quercetin. Blind docking revealed a second high-affinity site in the Fibronectin type II domain.Molecular dynamics simulations confirmed the stability of these complexes. In vitro studies showed that δ-cadinene significantly reduced MDA-MB-231 cell viability in a concentration-dependent manner, without affecting MCF10-A cells, and significantly inhibited invasion and MMP-2 activity after 24 h. Conclusions: δ-cadinene exhibits selective cytotoxic and anti-invasive activity in MDA-MB-231 cells, likely through dual inhibition of the catalytic and adhesion domains of MMP-2. These findings support δ-cadinene as a potential candidate for future therapeutic development in metastatic breast cancer. Full article

In recent years, the four main swine influenza A virus (IAV-S) subtypes circulating in swine in the EU have been H1avN1, H1huN2, H1N1pdm09, and H3N2. The latter emerged in 1984 from a reassortment event between a human seasonal H3N2 and H1avN1, and is currently detected at low prevalence in swine in Italy. Here, we describe nine H3N2 IAV-S isolates belonging to three novel genotypes, first detected in Italy in 2021, likely resulting from reassortment events between swine and human IAVs. The first genotype was characterized by a hemagglutinin (H3 HA) of human seasonal origin, a neuraminidase (N2 NA) derived from H1huN2 strains circulating in Italian swine, and an avian-like internal gene cassette (IGC). The second genotype differed in its IGC constellation: PB2, PB1, PA and NP segments were of pandemic origin (pdm09), while NS and M segments derived from the Eurasian avian-like lineage. The third genotype combined a human-derived H3, a Gent/84-derived N2, and a pdm09-origin IGC, except for an avian-like NS. This study aimed to characterize the genetic features of these novel H3huN2 and assess their epidemiological relevance, with implications for surveillance and control, improving preparedness and mitigating the risks posed by zoonotic influenza viruses. Full article

Influenza A virus pandemics pose a persistent global health threat, and emerging antiviral resistance underscores the critical importance of developing novel broad-spectrum therapeutic agents. Building on licorice’s (Glycyrrhiza spp.) historical use in traditional Chinese medicine for respiratory infections—as documented in the Chinese Guidelines for Diagnosis and Treatment of Influenza—and its demonstrated anti-SARS-CoV-2 activity, we identified licoflavone B as a potent anti-influenza agent, bridging ethnopharmacological knowledge with mechanistic validation. In this study, we identified licoflavone B, a natural flavonoid derived from licorice (Glycyrrhiza spp.), as a potent inhibitor of diverse influenza viruses, including multiple influenza A subtypes and type B virus. Mechanistic studies revealed that licoflavone B selectively targets the viral RNA-dependent RNA polymerase (RdRp), effectively suppressing viral replication. The compound exhibits a favorable selectivity index (SI = 14.9–29.9), indicating a promising therapeutic window. Molecular docking simulations identified potential binding interactions between licoflavone B and regions of the RdRp complex, which were further validated by dose-dependent inhibition of viral nucleoprotein (NP) and polymerase subunit PB2 expression in Western blot and immunofluorescence assays. In addition, licoflavone B maintained broad-spectrum antiviral activity against multiple influenza strains, including H1N1 (A/Puerto Rico/8/34), H3N2 (A/Darwin/9/2021), and a clinical influenza B isolate (B/Beijing/ZYY-B18/2018). These findings position licoflavone B as a promising lead compound for developing next-generation, broad-spectrum antiviral therapies against influenza and potentially other viruses. Full article

Background/Objectives: The development of a vaccine against highly pathogenic avian influenza viruses subtype A/H5 is an urgent task due to concerns about its pandemic potential. Methods: In this study, we have developed an experimental mRNA vaccine, mRNA-H5, encoding a modified hemagglutinin trimer of influenza virus A/turkey/Stavropol/320-01/2020 (H5N8). BALB/c mice were immunized with the mRNA-H5 vaccine using lipid nanoparticles (LNPs) and needle-free jet injection (JI). Subsequently, the immune response to vaccine was assessed using ELISA, microneutralization assay, and ICS methods, and a challenge study was conducted. Results: mRNA-H5 was shown to effectively stimulate specific humoral and T-cell immune responses. Moreover, mRNA-H5 delivered by LNPs and JI provided 100% protection of immunized mice against lethal challenge with homologous and heterologous strains of avian influenza virus (A/Astrakhan/3212/2020 (H5N8) and A/chicken/Magadan/14-7V/2022 (H5N1), respectively). Conclusions: The present results indicate that JI can be considered as an alternative to LNPs for mRNA delivery, and according to the literature, JI is safer than delivery using LNP. mRNA-H5 has potential as a vaccine against infection with highly pathogenic avian influenza A/H5 viruses with pandemic potential. Full article

PR/SET domain 2 (PRDM2)/RIZ is a member of the histone/protein methyltransferases (PRDMs) superfamily. Discovered to have the ability to bind retinoblastoma in the mid-1990s, PRDM2 was assumed to play a role in neuronal development. Like other family members characterized by a conserved N-terminal PR structural domain and a classical C2H2 zinc-finger array at the C-terminus, PRDM2 encodes two major protein types, the RIZ1 and RIZ2 isoforms. The two subtypes differ in the presence or absence of the PR domain: the RIZ1 subtype has the PR domain, whereas the RIZ2 subtype lacks it. The PR domain exhibits varying conservation levels across species and shares structural and functional similarities with the catalytic SET domain, defining histone methyltransferases. Functioning as an SET domain, the PR domain possesses protein-binding interfaces and acts as a lysine methyltransferase. The variable number of classic C2H2 zinc fingers at the C-terminus may mediate protein–protein, protein–RNA, or protein–DNA interactions. An imbalance in the RIZ1/RIZ2 mechanism may be an essential cause of malignant tumors, where PR-positive isoforms are usually lost or downregulated. Conversely, PR-negative isoforms are always present at higher levels in cancer cells. RIZ1 isoforms are also important targets for estradiol interaction with hormone receptors. PRDM2 can regulate gene transcription and expression combined with transcription factors and plays a role in the development of several systemic diseases through mRNA expression deletion, code-shift mutation, chromosomal deletion, and missense mutation occurrence. Thus, PRDM2 is a key indicator for disease diagnosis, but it lacks systematic summaries to serve as a reference for study. Therefore, this paper describes the structure and biological function of PRDM2 from the perspective of its role in various systemic diseases. It also organizes and categorizes its latest research progress to provide a systematic theoretical basis for a more in-depth investigation of the molecular mechanism of PRDM2’s involvement in disease progression and clinical practice. Full article

Avian influenza A viruses (AIVs) pose a significant pandemic threat due to their cross-species transmission potential. However, AIV surveillance at the critical “migratory birds–poultry-exposed population” interface remains limited. Between 2021 and 2024, we implemented a prospective One Health surveillance program around Nansi Lake, monitoring AIVs in migratory birds, poultry, and environmental samples, as well as serological investigations against representative AIVs among migratory birds or poultry-exposed subjects. AIVs were detected in 2.1% (30/1417) of migratory bird samples and 10.2% (100/978) of poultry samples. Among these, we identified ten highly pathogenic avian influenza (HPAI) H5 subtype viruses, one HPAI H7N9 virus, and five low pathogenic avian influenza (LPAI) H9N2 viruses. Phylogenetic analysis revealed evidence of frequent genomic reassortment events involving H5 subtype viruses among migratory birds, poultry, and humans. Serological investigation also suggested that both migratory birds and the poultry-exposed population had a higher risk of getting AIV infection than the general control population, especially against the H9N2 virus. Our study emphasizes the importance of strengthening continuous prospective surveillance of AIVs among migratory birds, poultry, and their exposed individuals to prevent and control potential outbreaks. Full article

The diagnosis of swine influenza A virus (swIAV) has to involve laboratory detection, as the clinical signs are not pathognomonic. Nasal swabs (NSs) have been the preferred sample material for swIAV PCR diagnostics, but oral fluid (OF) is a convenient alternative material. In this study, NSs and OFs from 35 Polish swine herds were collected and tested with real-time RT-PCR in order to assess swIAV circulation patterns in Poland and improve protocols for efficient, non-invasive and cost-effective swIAV surveillance in pig farms. The study showed that the swIAV RNA was detected in 65.7% of the tested farms. In total, 21.2% of NS pools and 48.6% of OF samples were positive for swIAV. The Ct values in NS pools and OFs were similar (p > 0.05), but a significant reduction (p < 0.05) in swIAV prevalence in NSs was observed in nursery pigs from farms applying swIAV vaccinations. Successful subtyping was achieved more effectively with OFs compared to NSs, and the H1avN2 was most prevalent subtype detected. The results emphasized that OF can be useful for monitoring swIAV and subtyping. However, OFs cannot replace NSs, which were more useful in the assessment of the effect of swIAV vaccinations in nursery pigs. Full article

Avian influenza A viruses (IAVs) pose a persistent threat to the poultry industry, causing substantial economic losses. Although traditional vaccines have helped reduce the disease burden, they typically rely on multivalent antigens, emphasize humoral immunity, and require intensive production. This study aimed to establish a genetically matched host–cell system to evaluate antigen-specific immune responses and identify conserved CD8+ T cell epitopes in avian influenza viruses. To this end, we developed an MHC class I genotype (B21)-matched host (Lohmann VALO SPF chicken) and cell vector (DF-1 cell line) model. DF-1 cells were engineered to express the hemagglutinin (HA) gene of clade 2.3.4.4b H5N1 either transiently or stably, and to stably express the matrix 1 (M1) and nucleoprotein (NP) genes of A/chicken/South Korea/SL20/2020 (H9N2, Y280-lineage). Following prime-boost immunization with HA-expressing DF-1 cells, only live cells induced strong hemagglutination inhibition (HI) and virus-neutralizing (VN) antibody titers in haplotype-matched chickens. Importantly, immunization with DF-1 cells transiently expressing NP induced stronger IFN-γ production than those expressing M1, demonstrating the platform’s potential for differentiating antigen-specific cellular responses. CD8+ T cell epitope mapping by mass spectrometry identified one distinct MHC class I-bound peptide from each of the HA-, M1-, and NP-expressing DF-1 cell lines. Notably, the identified HA epitope was conserved in 97.6% of H5-subtype IAVs, and the NP epitope in 98.5% of pan-subtype IAVs. These findings highlight the platform’s utility for antigen dissection and rational vaccine design. While limited by MHC compatibility, this approach enables identification of naturally presented epitopes and provides insight into conserved, functionally constrained viral targets. Full article

The H1N1 swine influenza viruses CQ91 and CQ445, isolated from pigs in China, exhibited distinct virulence in mice despite sharing similar genomic constellations. CQ91 demonstrated higher pathogenicity (MLD₅₀: 5.4 log₁₀ EID₅₀) and replication efficiency in mice compared to CQ445 (MLD₅₀: 6.6 log₁₀ EID₅₀). Through reverse genetics, we found that the attenuation of CQ445 was due to a single substitution of glutamic acid (E) with lysine (K) at position 343 in the PB2 protein. Introducing the CQ445-PB2 (343K) into CQ91 significantly reduced viral replication and pathogenicity in mice, while replacing CQ445-PB2 with CQ91-PB2 (343E) restored virulence. In vitro studies showed that the K343E mutation impaired viral replication in MDCK and A549 cells and reduced polymerase activity in minigenome assays. Mechanistically, the amino acid at position 343 in the PB2 affects the transcription stage of the viral replication process. Structural modeling indicated that the charge reversal caused by E343K altered local electrostatic interactions without major conformational changes. Phylogenetic analysis revealed that PB2-343E is highly conserved (>99.9%) in human and swine H1/H3 influenza viruses, suggesting that PB2-343E confers an adaptive advantage. This study identifies PB2-343E as a critical determinant of influenza virus pathogenicity in mammals, highlighting its role in host adaptation. Full article

Avian influenza virus (AIV) remains a persistent threat to both the poultry industry and human health. Among the AIV subtypes posing public health threats, H7N9 AIV is responsible for five epidemic waves of human infection in China. Here, a detection system based on a mouse model was established, which can simultaneously and quantitatively analyze the dynamic changes in the viral genomic RNA (vRNA), complementary RNA (cRNA), and messenger RNA (mRNA) of H7N9 AIV by using reverse transcription primers with tag sequences to reverse transcribe the three species of RNAs into corresponding cDNA templates, which are then absolutely quantified using the TaqMan quantitative PCR method. This system specifically targets the PB2 and NA genes and, for the first time, enables a spatiotemporal analysis of all three viral RNA species within an animal model. Our results revealed that H7N9 AIV exhibits characteristic replication kinetics, with all three species of viral RNAs showing a rapid increase followed by a certain degree of decline. This system offers a powerful tool for us to further advance our understanding of the replication dynamics of AIV in mice. Full article

A novel bivalent oral vaccine candidate against H5N1 and H9N2 avian influenza virus (AIV) was developed using Lactobacillus surface display technology without genetic modification. The hemagglutinin subunit 1 (HA1) antigens from both subtypes were fused to the surface layer-binding domain of Lactobacillus crispatus K313, expressed in Escherichia coli, and purified. Wild-type Lactobacillus johnsonii H31, isolated from chicken intestine, served as a delivery vehicle by adsorbing and stably displaying the HA1 proteins on its surface. This approach eliminates the need for bacterial engineering while utilizing lactobacilli’s natural capacity to protect surface-displayed antigens, as evidenced by HA1’s protease resistance. Mouse immunization studies demonstrated induction of strong systemic IgG and mucosal IgA responses against both H5N1 and H9N2 HA1. The system offers several advantages, including safety through non-GMO probiotics, potential for multivalent vaccine expansion, and intrinsic antigen protection by lactobacilli. These findings suggest this platform could enable development of cost-effective, multivalent AIV vaccines. Full article

This work aimed to evaluate two albumin affinity structure-containing peptide-radionuclide conjugate drugs, INER-PP-F11N-1 and INER-PP-F11N-2, for the diagnosis/treatment of cholecystokinin receptor subtype 2 (CCK2R)-overexpressing cancers. We developed In-111- and Lu-177-labeled INER-PP-F11N radiopharmaceuticals and compared them with the current PP-F11N to investigate metabolic stability, biodistribution, SPECT/CT imaging, and therapeutic responses in CCK2R-expressing tumor xenograft mice. The metabolic stability of [¹¹¹In]In/[¹⁷⁷Lu]Lu-INER-PP-F11N remained above 90% for up to 144 h after labeling, indicating that the compound is highly stable under in vitro conditions. INER-PP-F11N showed 27% and 11% higher cellular uptake and internalization than PP-F11N, respectively. In vivo SPECT/CT imaging confirmed that INER-PP-F11N could accumulate at the tumor site of mice 24 h after receiving the two radiopharmaceutical agents. Biodistribution analysis revealed a significantly greater tumor uptake and reduced accumulation of INER-PP-F11N in the kidneys compared with PP-F11N. Furthermore, INER-PP-F11N significantly inhibited the growth of the CCK2R-overexpressing tumors in mice. The INER-PP-F11N radiopharmaceutical was superior as a theragnostic agent compared with the current PP-F11N. Our study suggests that INER-PP-F11N may be an innovative radiopharmaceutical agent for CCK2R-overexpressing tumors. Full article

Avian influenza is an economically significant disease affecting poultry worldwide and is caused by influenza A viruses that can range from low to highly pathogenic strains. These viruses primarily target the respiratory, digestive, and nervous systems of birds, leading to severe outbreaks that threaten poultry production and pose zoonotic risks. The ectodomain of the avian influenza virus (AIV) matrix protein 2 (M2e), known for its high conservation across influenza strains, has emerged as a promising candidate for developing a universal influenza vaccine in a mouse model. However, the efficacy of such expression against poultry AIVs remains limited. The objective of this study was to evaluate the immunogenicity of nodavirus-like particles displaying the M2e proteins. In this study, three synthetic heterologous M2e genes originated from AIV strains H5N1, H9N2 and H5N2 were fused with the nodavirus capsid protein (NVC) of the giant freshwater prawn Macrobrachium rosenbergii (NVC-3xAvM2e) prior to immunogenicity characterisations in chickens. The expression vector pTRcHis-TARNA2 carrying the NVC-3xAvM2e gene cassette was introduced into E. coli TOP-10 cells. The recombinant proteins were purified, inoculated into one-week-old specific pathogen-free chickens subcutaneously and analysed. The recombinant protein NVC-3xAvM2e formed virus-like particles (VLPs) of approximately 25 nm in diameter when observed under a transmission electron microscope. Dynamic light scattering (DLS) analysis revealed that the VLPs have a polydispersity index (PDI) of 0.198. A direct ELISA upon animal experiments showed that M2e-specific antibodies were significantly increased in vaccinated chickens after the booster, with H5N1 M2e peptides having the highest mean absorbance value when compared with those of H9N2 and H5N2. A challenge study using low pathogenic AIV (LPAI) strain A/chicken/Malaysia/UPM994/2018 (H9N2) at 10^6.5 EID₅₀ showed significant viral load in the lung and cloaca, but not in the oropharyngeal of vaccinated animals when compared with the unvaccinated control group. Collectively, this study suggests that nodavirus-like particles displaying three heterologous M2e have the potential to provide protection against LPAI H9N2 in chickens, though the vaccine’s efficacy and cross-protection across different haemagglutinin (HA) subtypes should be further evaluated. Full article

Previously, we developed a porcine bronchial epithelial cell line designated as PBE cells and demonstrated that this cell line possesses functional Toll-like receptor 3 (TLR3), triggering the expressions of interferons (IFNs), antiviral factors, and inflammatory cytokines after its stimulation with the synthetic double-stranded ARN poly(I:C). In this work, we aimed to further characterize the PBE cell line as a reliable in vitro model for investigating swine influenza virus (SIV) infection and immunity. We evaluated the capacity of two SIV subtypes, H1N1 and H3N2, to replicate and induce cytopathic effects in PBE cells and to modulate the expressions of IFNs, antiviral factors, inflammatory cytokines, and negative regulators of the TLR signaling. We demonstrated that PBE cells are susceptible to both H1N1 and H3N2. SIV infected PBE cells inducing notable cytopathic effects as shown by the alteration of transepithelial electrical resistance (TEER) and cilia. Both SIV subtypes replicated in PBE cells in similar proportion and altered TEER values in comparable magnitudes. However, SIV H3N2 induced higher alterations of cilia than H1N1. SIV infection induced changes in all the immune factors evaluated in PBE cells. We detected quantitative differences when the subtypes H1N1 and H3N2 were compared. The fold expression changes of IFN-β, Mx1, Mx2, IFITM1, OAS1, OAS2, and OASL were higher in PBE cells infected with H3N2 than in cells challenged with H1N1. In addition, although both subtypes stimulated IL-8 expression, only the H3N2 induced IL-6 in infected PBE cells. SIV H1N1 and H3N2 also upregulated the expressions of the negative regulators A20, BCL-3, and MKP-1, while only H1N1 increased SIGIRR and Tollip. Immortalized respiratory cell lines from pigs can be useful in vitro systems for the study of viral infections and immune responses. These studies are of importance in the context of influenza infections not only for the agricultural field because pigs are natural hosts of these viruses but also because these animals serve as intermediate reservoirs of viruses that can threaten humans’ health. We demonstrated here that the PBE cell line can be a useful in vitro model to study SIV infection and immunity. Full article

The avian influenza virus, particularly the highly pathogenic H5N1 subtype, represents a significant public health threat due to its interspecies transmission potential and growing resistance to current antiviral therapies. To address this, the identification of novel and effective neuraminidase (NA) inhibitors is critical. In this study, an integrated in silico strategy was employed, beginning with the generation of an energy-optimized pharmacophore model (e-pharmacophore, ADDN) based on the reference inhibitor Zanamivir. A virtual screening of 47,781 natural compounds from the PubChem database was performed, followed by molecular docking validated through an enrichment assay. Promising hits were further evaluated via ADMET predictions, density functional theory (DFT) calculations to assess chemical reactivity, and molecular dynamics (MD) simulations to examine the stability of the ligand–protein complexes. Three lead compounds (C1: CID 102209473, C2: CID 85692821, and C3: CID 45379525) demonstrated strong binding affinity toward NA. Their ADMET profiles predicted favorable bioavailability and low toxicity. The DFT analyses indicated suitable chemical reactivity, particularly for C2 and C3. The MD simulations confirmed the structural stability of all three ligand–NA complexes, supported by robust and complementary intermolecular interactions. In contrast, Zanamivir exhibited limited hydrophobic interactions, compromising its binding stability within the active site. These findings offer a rational foundation for further experimental validation and the development of next-generation NA inhibitors derived from natural sources. Full article