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Annals of Internal Medicine Dec 2023In their article, Edelstein and colleagues provide the results of an observational study of virologic response in patients who received treatment with...
In their article, Edelstein and colleagues provide the results of an observational study of virologic response in patients who received treatment with nirmatrelvir–ritonavir (N-R) versus those who received no COVID-19 therapy. The editorialists discuss the findings and emphasize the need for further consideration of the dosage, timing, and duration of treatment to inform optimal use of N-R.
Topics: Humans; COVID-19; Ritonavir; COVID-19 Drug Treatment; Antiviral Agents
PubMed: 37956432
DOI: 10.7326/M23-2887 -
Science Advances Sep 2023PARP14 is a mono-ADP-ribosyl transferase involved in the control of immunity, transcription, and DNA replication stress management. However, little is known about the...
PARP14 is a mono-ADP-ribosyl transferase involved in the control of immunity, transcription, and DNA replication stress management. However, little is known about the ADP-ribosylation activity of PARP14, including its substrate specificity or how PARP14-dependent ADP-ribosylation is reversed. We show that PARP14 is a dual-function enzyme with both ADP-ribosyl transferase and hydrolase activity acting on both protein and nucleic acid substrates. In particular, we show that the PARP14 macrodomain 1 is an active ADP-ribosyl hydrolase. We also demonstrate hydrolytic activity for the first macrodomain of PARP9. We reveal that expression of a PARP14 mutant with the inactivated macrodomain 1 results in a marked increase in mono(ADP-ribosyl)ation of proteins in human cells, including PARP14 itself and antiviral PARP13, and displays specific cellular phenotypes. Moreover, we demonstrate that the closely related hydrolytically active macrodomain of SARS2 Nsp3, Mac1, efficiently reverses PARP14 ADP-ribosylation in vitro and in cells, supporting the evolution of viral macrodomains to counteract PARP14-mediated antiviral response.
Topics: Humans; Transferases; Poly(ADP-ribose) Polymerase Inhibitors; COVID-19; Antiviral Agents; Hydrolases; Poly(ADP-ribose) Polymerases
PubMed: 37703374
DOI: 10.1126/sciadv.adi2687 -
European Review For Medical and... Oct 2023In a previous study, we reported an increase of nasal nerve growth factor (NGF) in patients treated with high-pressure administration of sterile saline isotonic solution...
OBJECTIVE
In a previous study, we reported an increase of nasal nerve growth factor (NGF) in patients treated with high-pressure administration of sterile saline isotonic solution (HPpSIS). Herein we characterized the nasal mucosa in terms of innate immune response and cytokine signature, including antiviral properties. Potential NGF and antiviral benefits of HPpSIS were also discussed.
PATIENTS AND METHODS
Twenty (20) patients (11 males, 9 females; age range 30-75 years old) underwent HPpSIS and nasal samples were collected before and after treatment. Nasal scraping was used for morphological (smears and Quick May-Grunwald Giemsa staining, MGG), biochemical (Histamine, Serotonin; ELISA) and molecular (messenger RNA, mRNA) analyses. Amplification of transcripts specific for Toll-like receptor (TLR) 3 (TLR3), TLR7, TLR9, Interleukin-(IL) 18 (IL18), IL13, IL12, eosinophil-derived neurotoxin (EDN), Eosinophil Cationic Protein (ECP), γ Interferon (γIFN), tryptase and serotonin was performed using the 2-step real-time Reverse Transcription Polymerase Chain Reaction (RT-PCR). Clinical and laboratory data were analyzed and compared.
RESULTS
The clinical evaluation showed a protective effect of our therapy. Smears showed the presence of leucocytes, eosinophils (EOs) and mast cells (MCs), and increased immunoreactivity for ECP/RNase3 and EDN after HPpSIS. ELISA showed increased levels of Serotonin and EDN associated with unchanged levels of substance P(SP) and histamine. Increased eosinophil-derived neurotoxin eosinophil-derived neurotoxin (EDN) levels were confirmed by in situ fluorescent analysis. HPpSIS induced the upregulation of TLR3, TLR7 and TLR9 transcripts, while no changes were observed for Intercellular Adhesion Molecule 1 (ICAM1), IL18, Interleukin-15 (IL15) and IL12 transcripts nor for Interleukin-6 (IL6) and IL13. No changes were also observed for γIFN and EDN/RNase2 transcripts, while ECP/RNase3 transcripts were significantly upregulated after HPpSIS. Finally, tryptase transcripts were unchanged while serotonin transcripts were significantly increased after HPpSIS.
CONCLUSIONS
The clinical and biomolecular changes observed at the nasal mucosa due to HpSS treatment suggest the activation of an innate surveillance, by means of TLR transcription, and a possible anti-viral response due to EDN upregulation. It remains to be verified if NGF, known to be released locally upon HpSIS treatment, might in part be responsible for this local activation.
Topics: Male; Female; Humans; Adult; Middle Aged; Aged; Eosinophil-Derived Neurotoxin; Interleukin-18; Toll-Like Receptor 3; Tryptases; Nerve Growth Factor; Toll-Like Receptor 7; Toll-Like Receptor 9; Histamine; Interleukin-13; Serotonin; Eosinophil Cationic Protein; Eosinophils; Antiviral Agents; Interleukin-12
PubMed: 37843339
DOI: 10.26355/eurrev_202310_33953 -
Emerging Microbes & Infections Dec 2023Zoonotic transmission of coronaviruses (CoVs) poses a serious public health threat. Swine acute diarrhea syndrome coronavirus (SADS-CoV), originating from a bat...
Zoonotic transmission of coronaviruses (CoVs) poses a serious public health threat. Swine acute diarrhea syndrome coronavirus (SADS-CoV), originating from a bat HKU2-related CoV, causes devastating swine diseases and poses a high risk of spillover to humans. Currently, licensed therapeutics that can prevent potential human outbreaks are unavailable. Identifying the cellular proteins that restrict viral infection is imperative for developing effective interventions and therapeutics. We utilized a large-scale human cDNA screening and identified transmembrane protein 53 (TMEM53) as a novel cell-intrinsic SADS-CoV restriction factor. The inhibitory effect of TMEM53 on SADS-CoV infection was found to be independent of canonical type I interferon responses. Instead, TMEM53 interacts with non-structural protein 12 (NSP12) and disrupts viral RNA-dependent RNA polymerase (RdRp) complex assembly by interrupting NSP8-NSP12 interaction, thus suppressing viral RdRp activity and RNA synthesis. Deleting the transmembrane domain of TMEM53 resulted in the abrogation of TMEM53-NSP12 interaction and TMEM53 antiviral activity. Importantly, TMEM53 exhibited broad antiviral activity against multiple HKU2-related CoVs. Our findings reveal a novel role of TMEM53 in SADS-CoV restriction and pave the way to host-directed therapeutics against HKU2-related CoV infection.
Topics: Animals; Humans; Alphacoronavirus; Antiviral Agents; Coronavirus Infections; RNA-Dependent RNA Polymerase; Swine; Membrane Proteins
PubMed: 37584551
DOI: 10.1080/22221751.2023.2249120 -
Antiviral Therapy Aug 2023In endemic areas, hepatitis C virus (HCV)/hepatitis B virus (HBV) coinfection is common, and patients with coinfection have a higher risk of developing liver disease... (Review)
Review
In endemic areas, hepatitis C virus (HCV)/hepatitis B virus (HBV) coinfection is common, and patients with coinfection have a higher risk of developing liver disease such as hepatocellular carcinoma, liver fibrosis and cirrhosis. In such cases, HCV predominates, and HBV replication is suppressed by HCV. HCV core proteins and interferons that are activated by HCV are responsible for the suppression of HBV. Immunosuppression is also seen in patients with HCV and HBV coinfections. A decrease in HCV-neutralizing antibody response and circulation of Th1-like Tfh cells is observed in patients with HCV and HBV coinfection. Both viruses interacted in the liver, and treatment of HCV/HBV coinfection is genotype-based and complex due to the interaction of both viruses. In HCV-dominant cases, direct-acting antiviral drugs and peg interferon plus ribavirin are used for the treatment, with continuous monitoring of AST and ALT. HBV-dominant cases are less common and are treated with peg interferon and nucleoside nucleotide analogues with monitoring of AST and ALT. The SVR rate in HCV-HBV coinfection is higher than that in monoinfection when treated with direct-acting antiviral drugs. But there is a risk of reactivation of HBV during and after therapy. The rate of reactivation is lower in patients treated with direct-acting antiviral drugs as compared to those treated with peg interferon plus ribavirin. Biomarkers of HBV such as HBcrAg, HBV DNA and HBVpg RNA are not effective in the prediction of HBV reactivation; only the hepatitis B surface antigen titre can be used as a biomarker for HBV reactivation. HCV can also be reactive, but this is found in very rare cases in which HBV is present and is treated first.
Topics: Humans; Hepatitis B virus; Antiviral Agents; Coinfection; Hepacivirus; Hepatitis C, Chronic; Ribavirin; Liver Cirrhosis; Interferons; Liver Neoplasms
PubMed: 37489502
DOI: 10.1177/13596535231189643 -
Cell Reports Oct 2023The innate immune response must be terminated in a timely manner at the late stage of infection to prevent unwanted inflammation. The role of mA-modified RNAs and their...
The innate immune response must be terminated in a timely manner at the late stage of infection to prevent unwanted inflammation. The role of mA-modified RNAs and their binding partners in this process is not well known. Here, we develop an enzymolysis-based RNA pull-down (eRP) method that utilizes the immunoglobulin G-degrading enzyme of Streptococcus pyogenes (IdeS) to fish out mA-modified RNA-associated proteins. We apply eRP to capture the methylated single-stranded RNA (ssRNA) probe-associated proteins and identify YT521-B homology domain-containing 2 (YTHDC2) as the mA-modified interferon β (IFN-β) mRNA-binding protein. YTHDC2, induced in macrophages at the late stage of virus infection, recruits IFN-stimulated exonuclease ISG20 (IFN-stimulated exonuclease gene 20) to degrade IFN-β mRNA, consequently inhibiting antiviral innate immune response. In vitro and in vivo deficiency of YTHDC2 increases IFN-β production at the late stage of viral infection. Our findings establish an eRP method to effectively identify RNA-protein interactions and add mechanistic insight to the termination of innate response for maintaining homeostasis.
Topics: Animals; Exoribonucleases; RNA, Viral; Exonucleases; Immunity, Innate; Virus Diseases; Antiviral Agents; RNA, Messenger
PubMed: 37776518
DOI: 10.1016/j.celrep.2023.113192 -
Antiviral Research Sep 2023Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a respiratory virus that causes COVID-19 disease, with an estimated global mortality of approximately 2%....
Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a respiratory virus that causes COVID-19 disease, with an estimated global mortality of approximately 2%. While global response strategies, which are predominantly reliant on regular vaccinations, have shifted from zero COVID to living with COVID, there is a distinct lack of broad-spectrum direct acting antiviral therapies that maintain efficacy across evolving SARS-CoV-2 variants of concern. This is of most concern for immunocompromised and immunosuppressed individuals who lack robust immune responses following vaccination, and others at risk for severe COVID and long-COVID. RNA interference (RNAi) therapeutics induced by short interfering RNAs (siRNAs) offer a promising antiviral treatment option, with broad-spectrum antiviral capabilities unparalleled by current antiviral therapeutics and a high genetic barrier to antiviral escape. Here we describe novel siRNAs, targeting highly conserved regions of the SARS-CoV-1 and 2 genome of both human and animal species, with multi-variant antiviral potency against eight SARS-CoV-2 lineages - Ancestral VIC01, Alpha, Beta, Gamma, Delta, Zeta, Kappa and Omicron. Treatment with our siRNA resulted in significant protection against virus-mediated cell death in vitro, with >97% cell survival (P < 0.0001), and corresponding reductions of viral nucleocapsid RNA of up to 99.9% (P < 0.0001). When compared to antivirals; Sotrovimab and Remdesivir, the siRNAs demonstrated a more potent antiviral effect and similarly, when multiplexing siRNAs to target different viral regions simultaneously, an increased antiviral effect was observed compared to individual siRNA treatments (P < 0.0001). These results demonstrate the potential for a highly effective broad-spectrum direct acting antiviral against multiple SARS-CoV-2 variants, including variants resistant to antivirals and vaccine generated neutralizing antibodies.
Topics: Animals; Humans; RNA, Small Interfering; SARS-CoV-2; Antiviral Agents; Post-Acute COVID-19 Syndrome; COVID-19; Hepatitis C, Chronic; Antibodies, Neutralizing; Antibodies, Viral; Spike Glycoprotein, Coronavirus
PubMed: 37478918
DOI: 10.1016/j.antiviral.2023.105677 -
Molecular Therapy : the Journal of the... Sep 2023Virus-induced lung injury is associated with loss of pulmonary epithelial-endothelial tight junction integrity. While the alveolar-capillary membrane may be an indirect...
Virus-induced lung injury is associated with loss of pulmonary epithelial-endothelial tight junction integrity. While the alveolar-capillary membrane may be an indirect target of injury, viruses may interact directly and/or indirectly with miRs to augment their replication potential and evade the host antiviral defense system. Here, we expose how the influenza virus (H1N1) capitalizes on host-derived interferon-induced, microRNA (miR)-193b-5p to target occludin and compromise antiviral defenses. Lung biopsies from patients infected with H1N1 revealed increased miR-193b-5p levels, marked reduction in occludin protein, and disruption of the alveolar-capillary barrier. In C57BL/6 mice, the expression of miR-193b-5p increased, and occludin decreased, 5-6 days post-infection with influenza (PR8). Inhibition of miR-193b-5p in primary human bronchial, pulmonary microvascular, and nasal epithelial cells enhanced antiviral responses. miR-193b-deficient mice were resistant to PR8. Knockdown of occludin, both in vitro and in vivo, and overexpression of miR-193b-5p reconstituted susceptibility to viral infection. miR-193b-5p inhibitor mitigated loss of occludin, improved viral clearance, reduced lung edema, and augmented survival in infected mice. Our results elucidate how the innate immune system may be exploited by the influenza virus and how strategies that prevent loss of occludin and preserve tight junction function may limit susceptibility to virus-induced lung injury.
Topics: Humans; Animals; Mice; Influenza, Human; MicroRNAs; Occludin; Lung Injury; Tight Junctions; Viral Load; Influenza A Virus, H1N1 Subtype; Mice, Inbred C57BL; Antiviral Agents
PubMed: 37340634
DOI: 10.1016/j.ymthe.2023.06.011 -
PLoS Pathogens Sep 2023Emerging evidence indicates that HIV-1 hijacks host DNA damage repair (DDR) pathways to facilitate multiple facets of virus replication. Canonically, HIV-1 engages...
Emerging evidence indicates that HIV-1 hijacks host DNA damage repair (DDR) pathways to facilitate multiple facets of virus replication. Canonically, HIV-1 engages proviral DDR responses through the accessory protein Vpr, which induces constitutive activation of DDR kinases ATM and ATR. However, in response to prolonged DDR signaling, ATM directly induces pro-inflammatory NF-κB signaling and activates multiple members of the TRIM family of antiviral restriction factors, several of which have been previously implicated in antagonizing retroviral and lentiviral replication. Here, we demonstrate that the HIV-1 accessory protein Vif blocks ATM-directed DNA repair processes, activation of NF-κB signaling responses, and TRIM protein phosphorylation. Vif function in ATM antagonism occurs in clinical isolates and in common HIV-1 Group M subtypes/clades circulating globally. Pharmacologic and functional studies combine to suggest that Vif blocks Vpr-directed activation of ATM but not ATR, signifying that HIV-1 utilizes discrete strategies to fine-tune DDR responses that promote virus replication while simultaneously inhibiting immune activation.
Topics: Humans; HIV-1; NF-kappa B; Phosphorylation; Antiviral Restriction Factors; HIV Seropositivity; Antiviral Agents; Ataxia Telangiectasia Mutated Proteins
PubMed: 37669285
DOI: 10.1371/journal.ppat.1011634 -
Plant Signaling & Behavior Dec 2023Methyltransferase (MTase) enzymes catalyze the addition of a methyl group to a variety of biological substrates. MTase-like (METTL) proteins are Class I MTases whose...
Methyltransferase (MTase) enzymes catalyze the addition of a methyl group to a variety of biological substrates. MTase-like (METTL) proteins are Class I MTases whose enzymatic activities contribute to the epigenetic and epitranscriptomic regulation of multiple cellular processes. N-adenosine methylation (mA) is a common chemical modification of eukaryotic and viral RNA whose abundance is jointly regulated by MTases and METTLs, demethylases, and mA binding proteins. mA affects various cellular processes including RNA degradation, post-transcriptional processing, and antiviral immunity. Here, we used and plum pox virus (PPV), an RNA virus of the family, to investigated the roles of MTases in plant-virus interaction. RNA sequencing analysis identified MTase transcripts that are differentially expressed during PPV infection; among these, accumulation of a METTL gene was significantly downregulated. Two METTL transcripts (NbMETTL1 and NbMETTL2) were cloned and further characterized. Sequence and structural analyses of the two encoded proteins identified a conserved S-adenosyl methionine (SAM) binding domain, showing they are SAM-dependent MTases phylogenetically related to human METTL16 and FIONA1. Overexpression of NbMETTL1 and NbMETTL2 caused a decrease of PPV accumulation. In sum, our results indicate that METTL homologues participate in plant antiviral responses.
Topics: Humans; Methyltransferases; Nicotiana; Methylation; S-Adenosylmethionine; Antiviral Agents
PubMed: 37210738
DOI: 10.1080/15592324.2023.2214760