Targeted and stimuli-responsive drug delivery enhances therapeutic efficacy and minimizes undesirable side effects of cancer treatment. Although cellulose nanocrystals (CNCs) are used as drug carriers because of their robustness, spindle shape, biocompatibility, renewability, and nontoxicity, the lack of programmability and functionality of CNCs-based platforms hampers their application. Thus, high adaptability and the capacity to form dynamic 3D nanostructures of DNA may be advantageous, as they can provide functionalities such as target-specific and stimuli-responsive drug release.
View Article and Find Full Text PDFSignal Transduct Target Ther
May 2024
The composition of commensal bacteria plays a critical role in controlling immune responses in the intestine. Studies have shown that specific bacterial strains may have the capacity to enhance host immune defense against gastrointestinal viral infections. While norovirus is known to be the most common cause of gastroenteritis, leading to an estimated 200,000 deaths every year, identification of bacterial strains with protective effects against norovirus infection remains elusive.
View Article and Find Full Text PDFZika virus (ZIKV) has been circulating in human networks over 70 years since its first appearance in Africa, yet little is known about whether the viral 3'-terminal sequence and nonstructural (NS) protein diverged genetically from ancient ZIKV have different effects on viral replication and virulence in currently prevailing Asian lineage ZIKV. Here we show, by a reverse genetics approach using an infectious cDNA clone for a consensus sequence (Con1) of ZIKV, which represents Asian ZIKV strains, and another clone derived from the MR766 strain isolated in Uganda, Africa in 1947, that the 3'-end sequence -UUUCU-3' homogeneously present in MR766 genome and the -GUCU-3' sequence strictly conserved in Asian ZIKV isolates are functionally equivalent in viral replication and gene expression. By gene swapping experiments using the two infectious cDNA clones, we show that the NS1-5 proteins of MR766 enhance replication competence of ZIKV Con1.
View Article and Find Full Text PDFBackground: We assessed the safety and immunogenicity of two recombinant DNA vaccines for COVID-19: GX-19 containing plasmid DNA encoding the SARS-CoV-2 spike protein, and GX-19N containing plasmid DNA encoding the SARS-CoV-2 receptor-binding domain (RBD) foldon, nucleocapsid protein, and plasmid DNA encoding the spike protein.
Methods: Two open-label non-randomised phase 1 trials, one of GX-19 and the other of GX-19N were done at two hospitals in South Korea. We enrolled healthy adults aged 19-49 years for the GX-19 trial and healthy adults aged 19-54 years for the GX-19N trial.
In spite of the large number of repositioned drugs and direct-acting antivirals in clinical trials for the management of the ongoing COVID-19 pandemic, there are few cost-effective therapeutic options for severe acute respiratory syndrome (SARS) coronavirus 2 (SCoV2) infection. In this paper, we show that xanthorrhizol (XNT), a bisabolane-type sesquiterpenoid compound isolated from the Roxb., a ginger-line plant of the family , displays a potent antiviral efficacy in vitro against SCoV2 and other related coronaviruses, including SARS-CoV-1 (SCoV1) and a common cold-causing human coronavirus.
View Article and Find Full Text PDFWe report the genome sequences of two GH clade severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains isolated from nasopharyngeal swabs from patients with coronavirus disease 2019 (COVID-19) in South Korea. These strains had two mutations in the untranslated regions and seven nonsynonymous substitutions in open reading frames, compared with Wuhan/Hu-1/2019, showing 99.96% sequence identity.
View Article and Find Full Text PDFThe MERS-CoV isolated during the 2015 nosocomial outbreak in Korea showed distinctive differences in mortality and transmission patterns compared to the prototype MERS-CoV EMC strain belonging to clade A. We established a BAC-based reverse genetics system for a Korean isolate of MERS-CoV KNIH002 in the clade B phylogenetically far from the EMC strain, and generated a recombinant MERS-CoV expressing red fluorescent protein. The virus rescued from the infectious clone and KNIH002 strain displayed growth attenuation compared to the EMC strain.
View Article and Find Full Text PDFThe neoagarohexaose (NA6) is an oligosaccharide that is derived from agarose, the major component of red algae cell walls, by enzymatic hydrolysis. Here we show that NA6 is a noncanonical Toll-like receptor 4 (TLR4) agonist with antiviral activity against norovirus. Its TLR4 activation was dependent on myeloid differentiation factor 2 (MD2) and cluster of differentiation 14 (CD14), leading to interferon-β (IFN-β) and tumor necrosis factor-α (TNF-α) production.
View Article and Find Full Text PDFHepatitis C virus (HCV) infects ~71 million people worldwide, and 399,000 people die annually due to HCV-related liver cirrhosis and hepatocellular carcinoma. The use of direct-acting antivirals results in a sustained virologic response in >95% of patients with chronic HCV infection. However, several issues remain to be solved to eradicate HCV.
View Article and Find Full Text PDFUbiquinol-cytochrome c reductase (UQCRB), a subunit of the mitochondrial complex III, is highly expressed in tissues from colorectal cancer patients. Since UQCRB is highly expressed in colorectal cancer, we investigated miRNAs from mutant UQCRB-expressing cell lines to identify new miRNA biomarkers. After sequencing miRNAs in the mutant UQCRB-expressing cell lines, miR-4435 was selected as a potential biomarker candidate from the six up-regulated miRNAs.
View Article and Find Full Text PDFtRNA-derived RNA fragments (tRFs) have emerged as a new class of functional RNAs implicated in cancer, metabolic and neurological disorders, and viral infection. Yet our understanding of their biogenesis and functions remains limited. In the present study, through analysis of small RNA profile we have identified a distinct set of tRFs derived from pre-tRNA 3' trailers in the hepatocellular carcinoma cell line Huh7.
View Article and Find Full Text PDFThe kinase C-related kinase 2 (PRK2), which phosphorylates hepatitis C virus (HCV) RNA polymerase, is a proviral factor enhancing HCV replication. Here, we report on the in vivo anti-HCV efficacy of HA1077, which inhibits viral genome replication by targeting PRK2 and displays viral entry inhibitory activity by targeting Rho-associated kinase. HA1077 showed synergistic antiviral activity selectively with nonstructural protein 5 A (NS5A) inhibitors including daclatasvir (DCV).
View Article and Find Full Text PDFPoly-gamma-glutamic acid (γ-PGA), an extracellular biopolymer produced by Bacillus sp., is a non-canonical toll-like receptor 4 (TLR4) agonist. Here we show its antiviral efficacy against noroviruses.
View Article and Find Full Text PDFThe recognition of pathogen-derived ligands by pattern recognition receptors activates the innate immune response, but the potential interaction of quorum-sensing (QS) signaling molecules with host anti-viral defenses remains largely unknown. Here we show that the Vibrio vulnificus QS molecule cyclo(Phe-Pro) (cFP) inhibits interferon (IFN)-β production by interfering with retinoic-acid-inducible gene-I (RIG-I) activation. Binding of cFP to the RIG-I 2CARD domain induces a conformational change in RIG-I, preventing the TRIM25-mediated ubiquitination to abrogate IFN production.
View Article and Find Full Text PDFBackground: The gold standard for antinuclear antibody (ANA) screening is the indirect immunofluorescence (IIF) assay with human epithelial cells (HEp-2). However, a number of substantial disadvantages of manual IIF assays have highlighted the need for the automation and standardization of fluorescent ANA (FANA) testing. We evaluated the performance of EUROPattern Suite (Euroimmun AG, Germany), an automated FANA image analyzer, with regard to ANA detection and pattern recognition compared with conventional manual interpretation using the fluorescence microscopic IIF assay.
View Article and Find Full Text PDFSmall interfering RNA (siRNA) delivery can provide an effective therapy for treating viral diseases by silencing genes involved in viral replication. In this study, a liver-targeting formulation of lipidoid nanoparticle for delivery of siRNA that targets protein kinase C-related kinase 2 (PRK2) to inhibit hepatitis C virus (HCV) replication is reported. The most effective, minimally cytotoxic lipidoid for siRNA delivery to hepatic cells is identified from a small library of alkyl epoxide-polyamine conjugates.
View Article and Find Full Text PDFHuman norovirus (HuNoV) is the primary cause of viral gastroenteritis worldwide. Fresh blueberries are among high risk foods associated with norovirus related outbreaks. Therefore, it is important to assess intervention strategies to reduce the risk of foodborne illness.
View Article and Find Full Text PDFThe liver-specific microRNA miR-122, which has essential roles in liver development and metabolism, is a key proviral factor for hepatitis C virus (HCV). Despite its crucial role in the liver and HCV life cycle, little is known about the molecular mechanism of miR-122 expression regulation by HCV infection. Here, we show that the HCV core protein downregulates the abundance of miR-122 by promoting its destabilization via the inhibition of GLD-2, a non-canonical cytoplasmic poly(A) polymerase.
View Article and Find Full Text PDFHost-targeting antivirals have an advantage over direct-acting antivirals in that they have a high genetic barrier to resistance. Here, we describe in vivo anti-hepatitis C virus (HCV) efficacy of a potent siRNA targeting the protein kinase C-related kinase 2 (PRK2), which phosphorylates HCV NS5B RNA-dependent RNA polymerase and promotes HCV replication. PRK2-silencing reduced the phosphorylated NS5B level and resulted in inhibition of NS5B RdRp activity to decrease HCV genome abundance.
View Article and Find Full Text PDFThe hepatitis C virus (HCV) internal ribosome entry site (IRES) that directs cap-independent viral translation is a primary target for small interfering RNA (siRNA)-based HCV antiviral therapy. However, identification of potent siRNAs against HCV IRES by bioinformatics-based siRNA design is a challenging task given the complexity of HCV IRES secondary and tertiary structures and association with multiple proteins, which can also dynamically change the structure of this cis-acting RNA element. In this work, we utilized siRNA tiling approach whereby siRNAs were tiled with overlapping sequences that were shifted by one or two nucleotides over the HCV IRES stem-loop structures III and IV spanning nucleotides (nts) 277-343.
View Article and Find Full Text PDFBackground And Purpose: Hepatitis C virus (HCV) infection is responsible for various chronic inflammatory liver diseases. Here, we have identified a naturally occurring compound with anti-HCV activity and have elucidated its mode of antiviral action.
Experimental Approach: Luciferase reporter and real-time RT-PCR assays were used to measure HCV replication.
R-(-)-β-O-methylsynephrine (OMe-Syn) is a naturally occurring small molecule that was identified in a previous screen as an inhibitor of angiogenesis. In this study, we conducted two animal model experiments to investigate the in vivo antiangiogenic activity of OMe-Syn. OMe-Syn significantly inhibited angiogenesis in a transgenic zebrafish model as well as in a mouse retinopathy model.
View Article and Find Full Text PDFThe hepatitis C virus (HCV) RNA genome is replicated by an RNA replicase complex (RC) consisting of cellular proteins and viral nonstructural (NS) proteins, including NS5B, an RNAdependent RNA polymerase (RdRp) and key enzyme for viral RNA genome replication. The HCV RC is known to be associated with an intracellular membrane structure, but the cellular components of the RC and their roles in the formation of the HCV RC have not been well characterized. In this study, we took a proteomic approach to identify stomatin, a member of the integral proteins of lipid rafts, as a cellular protein interacting with HCV NS5B.
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