instruction:
In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.
question:
Herpes simplex virus (HSV) infections can be treated with direct acting antivirals like acyclovir and foscarnet, but long-term use can lead to drug resistance, which motivates research into broadly-acting antivirals that can provide a greater genetic barrier to resistance. Photodynamic inactivation (PDI) employs a photosensitizer, light, and oxygen to create a local burst of reactive oxygen species that inactivate microorganisms. The botanical plant extract Orthoquin TM is a powerful photosensitizer with antimicrobial properties. Here we report that Orthoquin also has antiviral properties. Photoactivated Orthoquin inhibited herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2) infection of target cells in a dose-dependent manner across a broad range of sub-cytotoxic concentrations. HSV inactivation required direct contact between Orthoquin and the inoculum, whereas pre-treatment of target cells had no effect. Orthoquin did not cause appreciable damage to viral capsids or premature release of viral genomes, as measured by qPCR for the HSV-1 genome. By contrast, immunoblotting for HSV-1 antigens in purified virion preparations suggested that higher doses of Orthoquin had a physical impact on certain HSV-1 proteins that altered protein mobility or antigen detection. Orthoquin PDI also inhibited the non-enveloped adenovirus (AdV) in a dose-dependent manner, whereas Orthoquin-mediated inhibition of the enveloped vesicular stomatitis virus (VSV) was light-independent. Together, these findings suggest that the broad antiviral effects of Orthoquin-mediated PDI may stem from damage to viral attachment proteins. facilitate attachment and entry into host cells. While HSV-1 and HSV-2 are similar, they share onlỹ 55% nucleotide identity. Lytic HSV infection of a cell begins with initial attachment to negatively charged cell surface heparan sulfate and chondroitin sulfate glycosaminoglycans, followed by stable attachment of viral glycoproteins to cell surface receptors and fusion of the viral envelope to the plasma membrane or internal membranes [2] . Fusion of viral and host membranes enables delivery of the viral nucleocapsid and tegument proteins to the cytoplasm. After the HSV nucleocapsid arrives at the nucleus and delivers the viral genome, HSV genes are expressed in an ordered temporal cascade. Viral egress requires primary envelopment of the genome-containing capsid at the inner nuclear membrane, fusion with the outer nuclear membrane and final envelopment at the trans-Golgi network. Mature virions then exit through the cellular secretory system. All stages of the HSV replication cycle offer potential targets for direct-acting antiviral (DAA) therapy. However, DAAs can be undermined by the emergence of drug resistant mutant viruses. Anti-HSV DAAs acyclovir and foscarnet offer examples of the hazards of drug resistance. These drugs interrupt HSV genome replication by different mechanisms of action. Acyclovir is a nucleoside analogue prodrug that selectively targets HSV infected cells through the action of the HSV thymidine kinase (TK) enzyme, which efficiently phosphorylates acyclovir and facilitates incorporation into nascent viral DNA genomes by the HSV DNA polymerase enzyme; incorporation of acyclovir into viral DNA terminates genome replication [3] . By contrast, the pyrophosphate analogue foscarnet blocks viral genome replication by directly inhibiting HSV DNA polymerase activity [4] . Though resistance to acyclovir occurs at a low prevalence (≤1%) in immunocompetent patients [5], immunocompromised patients experience much higher rates (4-10%) [6] . Unsurprisingly, resistance to acyclovir, and its derivatives, and to foscarnet, has been mapped to mutations in the viral thymidine kinase and the DNA polymerase catalytic subunit, respectively [7] . Currently, Abreva (n-docosanol) is the only over-the-counter topical antiviral for herpes labialis. Abreva is incorporated into the cellular plasma membrane and prevents fusion steps essential for HSV-1 entry into epithelial cells [8] . However, it must be applied repeatedly throughout the day due to rapid plasma membrane turnover and the subsequent loss of n-docosanol [9] . This host-targeted antiviral mechanism prevents development of viral resistance, but Abreva is only approved for perioral lesions, so there is a still a gap in treatment for lesions in other areas of the body. Like Abreva, there is potential for more broadly-acting antiviral drugs that exploit the physical structure of the HSV virion and block early stages of infection, such as attachment and penetration. In this study, we explored the potential of the plant-derived photosensitizing agent Orthoquin TM to mediate photodynamic inactivation (PDI) [10] of virions. The clinical utility of Orthoquin PDI of oral biofilms is an area of active investigation and there is clear potential for wider range of clinical applications. The basis of PDI is the photodynamic effect, which has been exploited in photodynamic therapy (PDT) [11, 12] for treatment of cancers [13] and age-related macular degeneration [14] . In PDT, photosensitizer compounds when exposed to visible light react with oxygen to generate reactive oxygen species (ROS) that include singlet oxygen [15] . ROS damage proteins, nucleic acids and lipids, which can lead to cell death. Some of the most well-known photosensitizing molecules for PDT are based on a tetrapyrrolic core and are found in naturally occurring pigments, such as heme, chlorophyll, and bacteriochlorophyll [16] . The accepted phototoxic mechanism for these types of photosensitizers involves the formation of an excited triplet state upon light absorption that can participate in electron (Type 1) or energy (Type 2) transfer processes. Type 1 electron transfer reactions typically lead to the formation of radical species like superoxide or hydroxyl radicals, whereas Type 2 energy transfer produces cytotoxic singlet oxygen. It is possible for a photosensitizer to initiate both Type 1 and 2 photoprocesses simultaneously, depending on the specific chemistry of the photosensitizing agent and its environment [16] . Due to the high reactivities and short lifetimes of oxidizing molecules, it is expected that only viral structures in close proximity to activated photosensitizing compounds will be affected.
answer:
Photodynamic Inactivation of Herpes Simplex Viruses


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The host antiviral response involves the induction of interferons and proinflammatory cytokines, but also the activation of cell death pathways, including apoptosis, to limit viral replication and spreading. This host defense is strictly regulated to eliminate the infection while limiting tissue damage that is associated with virus pathogenesis. Post-translational modifications, most notably phosphorylation, are key regulators of the antiviral defense implying an important role of protein phosphatases. Here, we investigated the role of the dual-specificity phosphatase 1 (DUSP1) in the host defense against human respiratory syncytial virus (RSV), a pathogenic virus of the Pneumoviridae family, and Sendai virus (SeV), a model virus being developed as a vector for anti-RSV vaccine. We found that DUSP1 is upregulated before being subjected to proteasomal degradation. DUSP1 does not inhibit the antiviral response, but negatively regulates virus-induced JNK/p38 MAPK phosphorylation. Interaction with the JNK-interacting protein 1 scaffold protein prevents dephosphorylation of JNK by DUSP1, likely explaining that AP-1 activation and downstream cytokine production are protected from DUSP1 inhibition. Importantly, DUSP1 promotes SeV-induced apoptosis and suppresses cell migration in RSVinfected cells. Collectively, our data unveils a previously unrecognized selective role of DUSP1 in the regulation of tissue damage and repair during infections by RSV and SeV. Respiratory syncytial virus (RSV) belongs to the Pneumoviridae family of large enveloped negative-sense ssRNA viruses that includes important human pathogens 1,2 . RSV is a leading cause of acute lower respiratory tract infections associated with morbidity and mortality in infants, children and elderly, but also adults of all-age with a compromised immune system, cardiopulmonary diseases or following transplantation 3,4 . The capacity of the host to mount an appropriate antiviral defense aimed at limiting virus replication and spreading is critical to determine the outcome of the infection. As a consequence, the inability of the host to sustain an antiviral response leads to failure in eradicating the infection. Conversely, uncontrolled duration or intensity of the response is harmful to the host and is associated with the development of virus-associated pathogenesis, chronic inflammatory diseases and various autoimmune diseases 5,6 . Therefore, these responses need to reach the ideal intensity and duration for efficient fighting of the infection while limiting tissue damage and promote tissue repair 7 . To this aim, the various components of the host antiviral defense, including the transcriptional induction of interferons (IFNs) and proinflammatory cytokines and chemokines, but also the activation of cell death pathways, such as apoptosis, are subjected to stringent regulation by both positive and negative mechanisms 8,9 . Published: xx xx xxxx OPEN www.nature.com/scientificreports/ 2 Scientific RepoRts | 7: 17388 | Upon virus entry and sensing by the cytosolic pathogen recognition receptors (PRRs) retinoic acid-inducible gene I (RIG-I) and melanoma differentiation-associated protein 5 (MDA-5), the mitochondrial membrane-associated adaptor (MAVS) coordinates multiple signalling pathways ultimately leading to the activation of the transcription factors IFN regulatory factors (IRF) 3/7, Nuclear Factor κB (NF-κB) and Activator Protein 1 (AP-1) 10-12 . Activation of IRF3 relies on a complex set of phosphorylations mainly mediated by the TANK-binding kinase 1 (TBK1)/ IκB kinase epsilon (IKKε) kinases 13-17 . NF-κB, mainly p65/p50, activation during SeV and RSV infections occurs through IκB kinase (IKK)-dependent phosphorylation of the NF-κB inhibitor protein IκBα and of the p65 subunit 18, 19 . The signaling cascade leading to AP-1 activation is more elusive, but ultimately results in the phosphorylation of the nuclear Activating Transcription Factor 2 (ATF-2) and c-Jun subunits by JNK and p38 Mitogen-Activated Protein Kinases (MAPKs) 10,20,21 . The activation of these transcription factors promotes the transcription of early antiviral genes, type I/III IFNs and proinflammatory cytokines and chemokines 12, 22, 23 . In response to IFNs, hundreds of interferon-stimulated genes (ISGs) are induced to limit virus replication through enhancement of virus detection and innate immune signaling, cytoskeleton remodelling, inhibition of protein translation, induction of apoptosis, amongst other antiviral functions 24-26 . These same PRRs have also been shown to activate IFN-independent cell death pathways, including apoptosis 8 . Post-translational modifications (PTMs), including phosphorylation, ubiquitylation and acetylation, of signal transduction proteins involved in the pathways engaged downstream of virus sensing are crucial to reach a fine-tuned regulation of the innate immune response 27 . In light of the very well documented importance of phosphorylation PTMs in the regulation of the antiviral response, the protein phosphatases negatively regulating the signaling events have started to be identified. The exact role of the Ser/Thr protein phosphatase 1 (PP1) in the antiviral response remains elusive as PP1α and PP1γ were found to dephosphorylate MDA-5 and RIG-I leading to their activation 28 , while they were also described to be responsible for the dephosphorylation of key C-terminal phosphoresidues of IRF3 leading to its inhibition 29 . Most likely reflecting the complexity of IRF3 regulation through phosphorylation at multiple C-terminal phosphoacceptor sites, two other phosphatases, the Ser/Thr protein phosphatase 2 (PP2A) and MAPK phosphatase (MKP) 5, dephosphorylate IRF3 to terminate its activation 30-32 . The Ser/Thr protein phosphatase, Mg 2+ /Mn 2+ -dependent (PPM) 1B acts as a TBK1 phosphatase to inhibit IRF3 activation, while PPM1A targets both TBK1/IKKε and MAVS for dephosphorylation to negatively regulate the antiviral response 33,34 . In the present study, we sought to address the role of the MKP-1/DUSP1 dual phosphatase (referred to thereafter as DUSP1) in the regulation of the host-defense against RSV and Sendai virus (SeV), a model paramyxovirus that is currently evaluated as a replication-competent backbone for the development of an RSV vaccine 3 . We demonstrate that DUSP1 is a negative regulator of RSV-and SeV-induced JNK/p38 MAPK phosphorylation. However, this function is neither linked to the inhibition of the antiviral response nor to the induction of a cytokine and chemokine response elicited during virus infection. Interestingly, we found that interaction of JNK by the JNK interacting protein (JIP) 1 scaffold protein, previously shown to be critical for AP-1 and downstream cytokine production specifically, protects JNK from dephosphorylation by DUSP1. Although we confirmed that a JNK/p38 signalling module is involved in the induction of virus-induced apoptosis, our data suggests that DUSP1 has a pro-apoptotic function independently of JNK and p38 during SeV infection. Finally, we found that DUSP1 dampens cell migration during RSV infection. Altogether, these findings point to a previously unrecognized role of DUSP1 in functions that have an impact on virus-associated tissue damage and repair.
answer:
DUSP1 regulates apoptosis and cell migration, but not the JIP1- protected cytokine response, during Respiratory Syncytial Virus and Sendai Virus infection OPEN


question:
Most of the modern techniques used for identification of viral-induced disease are based on identification of viral antigens and/or nucleic acids in patient's blood. Diagnosis in the field or in remote locations can be challenging and alternatively samples are shipped to diagnostic labs for testing. Shipments must occur under controlled temperature conditions to prevent loss of sample integrity. We have tested the ability of magnetic Nanotrap ® (NT) particles to improve stability and detection of Venezuelan equine encephalitis virus (VEEV), viral capsid protein, and viral genomic RNA in whole human blood at elevated temperature and prolonged storage conditions. NT particles have previously been shown to capture and enrich multiple pathogens including respiratory syncytial virus, influenza virus, coronavirus, and Rift Valley fever virus. Our study indicates that samples incubated with NT particles had detectable levels of infectious VEEV in blood equal to or greater than samples without NT treatment across all temperatures. Viral RNA detection was increased in the presence of NT particles at later time points (72 h) and higher temperature (40 • C) conditions. Likewise, detection of VEEV capsid protein was enhanced in the presence of NT particles up to 72 h at 40 • C. Finally, we intranasally infected C3H mice with TC-83, the live attenuated vaccine strain of VEEV, and demonstrated that NT particles could substantially increase the detection of VEEV capsid in infected blood incubated up to 72 h at 40 • C. Samples without NT particles had undetectable capsid protein levels. Taken together, our data demonstrate the ability of NT particles to preserve and enable detection of VEEV in human and mouse blood samples over time and at elevated temperatures.
answer:

Magnetic Nanotrap Particles Preserve the Stability of Venezuelan Equine Encephalitis Virus in Blood for Laboratory Detection