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The airway is the major entry route of pathogens due to continuous gas exchange with the environment. In particular, the nasal epithelial layer is the common site of airborne mucotropic virus infections. The inflammatory response to such infections must be tightly controlled due to its non-specific nature. Unrestrained inflammation breaks down the physiological mucosal defense system and leads to secondary bacterial or fungal infections. Chronic rhinosinusitis (CRS) is a prevalent inflammatory disease that compromises quality of life. In spite of its importance in the initiation of inflammation, the role of interferon signaling in nasal airway epithelial cells is largely unknown. We analyzed the expression of interferon signaling genes using clinical lavage specimens and nasal airway epithelial cells collected from CRS patients and controls. Basal expression of IFNAs, IKBKE, STAT1, and some CXC chemokines was elevated in samples from CRS patients. In subsequent in vitro studies, we found IKKε to be the key molecule and augmented CXCL10 secretion. Based on our findings and review of the literature, we hypothesized that high levels of IKKε might induce intractable inflammation via CXCL10. We tested the hypothesis in an animal model and found not only that IKKε induced severe eosinophilic inflammation with CXCL10 over-production, but also that inhibition of IKKε resolved the inflammation., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Hepatitis C virus (HCV) affects 2-3% of the global population. Approximately one-quarter of acute infections cause chronic hepatitis that leads to liver cirrhosis or hepatocellular carcinoma. The major obstacle of current research is the extremely narrow host tropism of HCV. A single HCV strain can replicate in the Huh7 human hepatoma cell line. Huh7 cells can be adapted under selective pressure in vitro to identify host factors that influence viral replication. Here, we extended this strategy to the in vivo condition and generated a series of cell lines by multiple rounds of adaptation in immunocompromised mice. Adaptation increased the cellular resistance to HCV infection. Microarray analyses revealed that the expression levels of several genes were associated with HCV resistance. Notably, up-regulation of the mRNA encoding cysteine-rich secretory protein 3 (CRISP3), a glycoprotein with unknown function that is secreted from multiple exocrine glands, was correlated with HCV resistance. The presence of CRISP3 in the culture medium limited HCV replication at the early phase of infection., (Copyright © 2014 Elsevier Inc. All rights reserved.)

A major concern of antiviral therapy using small interfering RNAs (siRNAs) targeting RNA viral genome is high sequence diversity and mutation rate due to genetic instability. To overcome this problem, it is indispensable to design siRNAs targeting highly conserved regions. We thus designed CAPSID (Convenient Application Program for siRNA Design), a novel bioinformatics program to identify siRNAs targeting highly conserved regions within RNA viral genomes. From a set of input RNAs of diverse sequences, CAPSID rapidly searches conserved patterns and suggests highly potent siRNA candidates in a hierarchical manner. To validate the usefulness of this novel program, we investigated the antiviral potency of universal siRNA for various Human enterovirus B (HEB) serotypes. Assessment of antiviral efficacy using Hela cells, clearly demonstrates that HEB-specific siRNAs exhibit protective effects against all HEBs examined. These findings strongly indicate that CAPSID can be applied to select universal antiviral siRNAs against highly divergent viral genomes.

Coxsackievirus A24 (CVA24) is responsible for acute hemorrhagic conjunctivitis, a highly contagious eye disease for which no prevention or treatment is currently available. We thus assessed the antiviral potential of a small interfering RNA (siRNA) targeting CVA24. HeLa cells with or without four different siRNAs complementary to 2C or 3D genome region, were challenged with various CVA24s. Among several siRNAs, a siRNA targeting the highly conserved genome region called the cis-acting replication element (CVA24-CRE), was the only siRNA that decreased virus replication and subsequent cytotoxicity by both CVA24 variant and clinical isolates. Furthermore, CVA24-CRE had effective antiviral activity against CVA24 in primary human conjunctival cells. In addition, CVA24-CRE was highly resistant to the emergence of genetically altered escape mutants. Collectively, the present study provides evidence that CVA24-CRE targeting a conserved viral genome region had universal, prolonged anti-CVA24 activity. This siRNA may thus hold a potential to act clinically as a novel anti-CVA24 agent.

Gelsolin consists of six related domains (G1-G6) and the C-terminal half (G4-G6) acts as a calcium sensor during the activation of the whole molecule, a process that involves large domain movements. In this study, we used targeted molecular dynamics simulations to elucidate the conformational transitions of G4-G6 at an atomic level. Domains G4 and G6 are initially ruptured, followed by a rotation of G6 by approximately 90 degrees , which is the dominant conformational change. During this period, local conformational changes occur at the G4 and G5 calcium-binding sites, facilitating large changes in interdomain distances. Alterations in the binding affinities of the calcium ions in these three domains appear to be related to local conformational changes at their binding sites. Analysis of the relative stabilities of the G4-G6-bound calcium ions suggests that they bind first to G6, then to G4, and finally to G5.