Therapeutic Exploitation of Viral Interference

2020 ◽  
Vol 20 (4) ◽  
pp. 423-432 ◽  
Author(s):  
Imre Kovesdi ◽  
Tibor Bakacs
Keyword(s):  
Broad Spectrum ◽  
Viral Infections ◽  
Viral Vector ◽  
Antiviral Treatment ◽  
Type I ◽  
Virus Infections ◽  
Emerging Viruses ◽  
Viral Interference ◽  
Pathogenic Virus ◽  
Hepatitis C Rna

: Viral interference, originally, referred to a state of temporary immunity, is a state whereby infection with a virus limits replication or production of a second infecting virus. However, replication of a second virus could also be dominant over the first virus. In fact, dominance can alternate between the two viruses. Expression of type I interferon genes is many times upregulated in infected epithelial cells. Since the interferon system can control most, if not all, virus infections in the absence of adaptive immunity, it was proposed that viral induction of a nonspecific localized temporary state of immunity may provide a strategy to control viral infections. Clinical observations also support such a theory, which gave credence to the development of superinfection therapy (SIT). SIT is an innovative therapeutic approach where a non-pathogenic virus is used to infect patients harboring a pathogenic virus. : For the functional cure of persistent viral infections and for the development of broad- spectrum antivirals against emerging viruses a paradigm shift was recently proposed. Instead of the virus, the therapy should be directed at the host. Such a host-directed-therapy (HDT) strategy could be the activation of endogenous innate immune response via toll-like receptors (TLRs). Superinfection therapy is such a host-directed-therapy, which has been validated in patients infected with two completely different viruses, the hepatitis B (DNA), and hepatitis C (RNA) viruses. SIT exerts post-infection interference via the constant presence of an attenuated non-pathogenic avian double- stranded (ds) RNA viral vector which boosts the endogenous innate (IFN) response. SIT could, therefore, be developed into a biological platform for a new “one drug, multiple bugs” broad-spectrum antiviral treatment approach.

scholarly journals Pluripotent Stem Cell-Based Models: A Peephole into Virus Infections during Early Pregnancy

Cells ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 542 ◽  
Author(s):  
Claudia Claus ◽  
Matthias Jung ◽  
Judith M. Hübschen
Keyword(s):  
Stem Cell ◽  
Human Development ◽  
Pluripotent Stem Cell ◽  
Viral Infections ◽  
Clinical Symptoms ◽  
Antiviral Treatment ◽  
Treatment Options ◽  
Virus Infections ◽  
Emerging Viruses ◽  
Congenital Rubella

The rubella virus (RV) was the first virus shown to be teratogenic in humans. The wealth of data on the clinical symptoms associated with congenital rubella syndrome is in stark contrast to an incomplete understanding of the forces leading to the teratogenic alterations in humans. This applies not only to RV, but also to congenital viral infections in general and includes (1) the mode of vertical transmission, even at early gestation, (2) the possible involvement of inflammation as a consequence of an activated innate immune response, and (3) the underlying molecular and cellular alterations. With the progress made in the development of pluripotent stem cell-based models including organoids and embryoids, it is now possible to assess congenital virus infections on a mechanistic level. Moreover, antiviral treatment options can be validated, and newly emerging viruses with a potential impact on human embryonal development, such as that recently reflected by the Zika virus (ZIKV), can be characterized. Here, we discuss human cytomegalovirus (HCMV) and ZIKV in comparison to RV as viruses with well-known congenital pathologies and highlight their analysis on current models for the early phase of human development. This includes the implications of their genetic variability and, as such, virus strain-specific properties for their use as archetype models for congenital virus infections. In this review, we will discuss the use of induced pluripotent stem cells (iPSC) and derived organoid systems for the study of congenital virus infections with a focus on their prominent aetiologies, HCMV, ZIKV, and RV. Their assessment on these models will provide valuable information on how human development is impaired by virus infections; it will also add new insights into the normal progression of human development through the analysis of developmental pathways in the context of virus-induced alterations. These are exciting perspectives for both developmental biology and congenital virology.

scholarly journals Fludarabine Inhibits Infection of Zika Virus, SFTS Phlebovirus, and Enterovirus A71

Viruses ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 774
Author(s):  
Chengfeng Gao ◽  
Chunxia Wen ◽  
Zhifeng Li ◽  
Shuhan Lin ◽  
Shu Gao ◽  
...  
Keyword(s):  
Broad Spectrum ◽  
Zika Virus ◽  
Therapeutic Agent ◽  
Viral Infections ◽  
Rna Virus ◽  
Emerging Viruses ◽  
Enterovirus A71 ◽  
Ic50 Values ◽  
High Doses ◽  
Severe Fever

Viral infections are one of the leading causes in human mortality and disease. Broad-spectrum antiviral drugs are a powerful weapon against new and re-emerging viruses. However, viral resistance to existing broad-spectrum antivirals remains a challenge, which demands development of new broad-spectrum therapeutics. In this report, we showed that fludarabine, a fluorinated purine analogue, effectively inhibited infection of RNA viruses, including Zika virus, Severe fever with thrombocytopenia syndrome virus, and Enterovirus A71, with all IC50 values below 1 μM in Vero, BHK21, U251 MG, and HMC3 cells. We observed that fludarabine has shown cytotoxicity to these cells only at high doses indicating it could be safe for future clinical use if approved. In conclusion, this study suggests that fludarabine could be developed as a potential broad-spectrum anti-RNA virus therapeutic agent.

scholarly journals First-in-Woman Safety, Tolerability, and Pharmacokinetics of Orally Administered GS-441524: A Broad-Spectrum Antiviral Treatment for COVID-19

2021 ◽  
Author(s):  
Victoria Yan
Keyword(s):  
Severe Acute Respiratory Syndrome ◽  
Broad Spectrum ◽  
Half Life ◽  
Maximum Concentration ◽  
Viral Infections ◽  
Clinical Laboratory ◽  
Antiviral Treatment ◽  
Oral Solution ◽  
Healthy Human

GS-441524 is a nucleoside analogue with broad-spectrum antiviral activity against RNA viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and feline coronavirus (FCoV). GS-441524 is the main circulating metabolite following intravenous administration of remdesivir (Veklury®), with a plasma half-life of approximately 24 hours. The safety, tolerability, and pharmacokinetics of GS-441524 was evaluated in a healthy human volunteer (N=1) when administered directly as an oral solution (750 mg) once daily for 7 days (Part 1) and 3 times daily for 3 days (Part 2). In Part 1 of the study, the effect of food on the absorption of GS-441524 was also evaluated. GS-441524 appeared rapidly in plasma, with an average time of maximum concentration of 0.5 hours during once-per-day dosing and exhibited an initial half-life phase of approximately 3.3 hours in the fasted state. Negligible accumulation was observed during part 1 of the multiday study. In Part 2 of the study, GS-441524 was administered 3 times daily, every 3 hours. A 2-4-fold accumulation of GS-441524 was observed approximately 3 hours after the third dose was administered, with a time of maximum concentration of 9 hours and a maximum concentration of 12.01 µM, exceeding the concentration reported to eradicate SARS-CoV-2 in vitro. For the duration of the study, GS-441524 was well-tolerated. There were no treatment-related adverse events and no clinically significant findings in clinical laboratory, vital signs, or electrocardiography. Taken together, these results demonstrate the safety and viability of orally administered GS-441524 for the treatment of COVID-19 and emerging viral infections.

scholarly journals Nasopharyngeal Type-I Interferon for Immediately Available Prophylaxis Against Emerging Respiratory Viral Infections

2021 ◽  
Vol 12 ◽  
Author(s):  
Amos C. Lee ◽  
Yunjin Jeong ◽  
Sumin Lee ◽  
Haewook Jang ◽  
Allen Zheng ◽  
...  
Keyword(s):  
Interferon Beta ◽  
Viral Infections ◽  
Respiratory Infections ◽  
Type I ◽  
Emerging Viruses ◽  
Respiratory Viral Infection ◽  
Respiratory Viral Infections ◽  
Viral Respiratory Infections ◽  
Viral Respiratory

In addition to SARS-CoV-2 and its variants, emerging viruses that cause respiratory viral infections will continue to arise. Increasing evidence suggests a delayed, possibly suppressed, type 1 interferon (IFN-I) response occurs early during COVID-19 and other viral respiratory infections such as SARS and MERS. These observations prompt considering IFN-β as a prophylactic or early intervention for respiratory viral infections. A rationale for developing and testing intranasal interferon beta (IFN-β) as an immediately available intervention for new respiratory viral infections that will arise unexpectedly in the future is presented and supported by basic and clinical trial observations. IFN-β prophylaxis could limit the spread and consequences of an emerging respiratory viral infection in at-risk individuals while specific vaccines are being developed.

scholarly journals Screening for Anti-Influenza Actives of Prefractionated Traditional Chinese Medicines

2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Qianli Kang ◽  
Yanyan Wang ◽  
Qinghua Cui ◽  
Lili Gong ◽  
Yong Yang ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Ebola Virus ◽  
Antiviral Treatment ◽  
Traditional Chinese Medicines ◽  
Virus Infections ◽  
Clinical Practices ◽  
Emerging Viruses ◽  
Gaussia Luciferase ◽  
Chinese Medicines ◽  
Antiviral Activities

Traditional Chinese medicines (TCMs) have proven to possess advantages in counteracting virus infections according to clinical practices. It’s therefore of great value to discover novel antivirals from TCMs. In this paper, One hundred medicinal plants which have been included in TCM prescriptions for antiviral treatment were selected and prefractionated into 5 fractions each by sequentially using cyclohexane, dichloromethane, ethyl acetate, n-butanol, and water. 500 TCM-simplified extracts were then subjected to a phenotypic screening using a recombinant IAV expressing Gaussia luciferase. Ten TCM fractions were identified to possess antiviral activities against influenza virus. The IC50’s of the hit fractions range from 1.08 to 6.45 μg/mL, while the SIs, from 7.52 to 98.40. Furthermore, all the ten hit fractions inhibited the propagation of progeny influenza virus significantly at 20 μg/mL. The hit TCM fractions deserve further isolation for responsible constituents leading towards anti-influenza drugs. Moreover, a library consisting of 500 simplified TCM extracts was established, facilitating antiviral screening in quick response to emerging and re-emerging viruses such as Ebola virus and current SARS-CoV-2 pandemic.

scholarly journals Activity of and Effect of Subcutaneous Treatment with the Broad-Spectrum Antiviral Lectin Griffithsin in Two Laboratory Rodent Models

2013 ◽  
Vol 58 (1) ◽  
pp. 120-127 ◽  
Author(s):  
Christopher Barton ◽  
J. Calvin Kouokam ◽  
Amanda B. Lasnik ◽  
Oded Foreman ◽  
Alexander Cambon ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Broad Spectrum ◽  
Ebola Virus ◽  
Viral Infections ◽  
Antiviral Treatment ◽  
Enveloped Viruses ◽  
Minimal Toxicity ◽  
Human T Cell ◽  
Long Term Treatment ◽  
Hiv 1

ABSTRACTGriffithsin (GRFT) is a red-alga-derived lectin that binds the terminal mannose residues of N-linked glycans found on the surface of human immunodeficiency virus type 1 (HIV-1), HIV-2, and other enveloped viruses, including hepatitis C virus (HCV), severe acute respiratory syndrome coronavirus (SARS-CoV), and Ebola virus. GRFT displays no human T-cell mitogenic activity and does not induce production of proinflammatory cytokines in treated human cell lines. However, despite the growing evidence showing the broad-spectrum nanomolar or better antiviral activity of GRFT, no study has reported a comprehensive assessment of GRFT safety as a potential systemic antiviral treatment. The results presented in this work show that minimal toxicity was induced by a range of single and repeated daily subcutaneous doses of GRFT in two rodent species, although we noted treatment-associated increases in spleen and liver mass suggestive of an antidrug immune response. The drug is systemically distributed, accumulating to high levels in the serum and plasma after subcutaneous delivery. Further, we showed that serum from GRFT-treated animals retained antiviral activity against HIV-1-enveloped pseudoviruses in a cell-based neutralization assay. Overall, our data presented here show that GRFT accumulates to relevant therapeutic concentrations which are tolerated with minimal toxicity. These studies support further development of GRFT as a systemic antiviral therapeutic agent against enveloped viruses, although deimmunizing the molecule may be necessary if it is to be used in long-term treatment of chronic viral infections.

scholarly journals Interferon-Stimulated Gene (ISG)-Expression Screening Reveals the Specific Antibunyaviral Activity of ISG20

2018 ◽  
Vol 92 (13) ◽  
Author(s):  
Junjie Feng ◽  
Arthur Wickenhagen ◽  
Matthew L. Turnbull ◽  
Veronica V. Rezelj ◽  
Felix Kreher ◽  
...  
Keyword(s):  
Viral Infections ◽  
Rhesus Macaques ◽  
Type I ◽  
Emerging Viruses ◽  
Content Type ◽  
Expression Screening ◽  
Interferon Stimulated Genes ◽  
Life Threatening

ABSTRACT Bunyaviruses pose a significant threat to human health, prosperity, and food security. In response to viral infections, interferons (IFNs) upregulate the expression of hundreds of interferon-stimulated genes (ISGs), whose cumulative action can potently inhibit the replication of bunyaviruses. We used a flow cytometry-based method to screen the ability of ∼500 unique ISGs from humans and rhesus macaques to inhibit the replication of Bunyamwera orthobunyavirus (BUNV), the prototype of both the Peribunyaviridae family and the Bunyavirales order. Candidates possessing antibunyaviral activity were further examined using a panel of divergent bunyaviruses. Interestingly, one candidate, ISG20, exhibited potent antibunyaviral activity against most viruses examined from the Peribunyaviridae , Hantaviridae , and Nairoviridae families, whereas phleboviruses ( Phenuiviridae ) largely escaped inhibition. Similar to the case against other viruses known to be targeted by ISG20, the antibunyaviral activity of ISG20 is dependent upon its functional RNase activity. Through use of an infectious virus-like particle (VLP) assay (based on the BUNV minigenome system), we confirmed that gene expression from all 3 viral segments is strongly inhibited by ISG20. Using in vitro evolution, we generated a substantially ISG20-resistant BUNV and mapped the determinants of ISG20 sensitivity/resistance. Taking all the data together, we report that ISG20 is a broad and potent antibunyaviral factor but that some bunyaviruses are remarkably ISG20 resistant. Thus, ISG20 sensitivity/resistance may influence the pathogenesis of bunyaviruses, many of which are emerging viruses of clinical or veterinary significance. IMPORTANCE There are hundreds of bunyaviruses, many of which cause life-threatening acute diseases in humans and livestock. The interferon (IFN) system is a key component of innate immunity, and type I IFNs limit bunyaviral propagation both in vitro and in vivo . Type I IFN signaling results in the upregulation of hundreds of IFN-stimulated genes (ISGs), whose concerted action generates an “antiviral state.” Although IFNs are critical in limiting bunyaviral replication and pathogenesis, much is still unknown about which ISGs inhibit bunyaviruses. Using ISG-expression screening, we examined the ability of ∼500 unique ISGs to inhibit Bunyamwera orthobunyavirus (BUNV), the prototypical bunyavirus. Using this approach, we identified ISG20, an interferon-stimulated exonuclease, as a potent inhibitor of BUNV. Interestingly, ISG20 possesses highly selective antibunyaviral activity, with multiple bunyaviruses being potently inhibited while some largely escape inhibition. We speculate that the ability of some bunyaviruses to escape ISG20 may influence their pathogenesis.

scholarly journals Long Noncoding RNAs as Emerging Regulators of COVID-19

2021 ◽  
Vol 12 ◽  
Author(s):  
Qinzhi Yang ◽  
Fang Lin ◽  
Yanan Wang ◽  
Min Zeng ◽  
Mao Luo
Keyword(s):  
Viral Infections ◽  
Immune Escape ◽  
Noncoding Rnas ◽  
Incidence Rates ◽  
Long Noncoding Rnas ◽  
Type I Interferons ◽  
Future Research ◽  
Type I ◽  
Virus Infections ◽  
Underlying Mechanisms

Coronavirus disease 2019 (COVID-19), which has high incidence rates with rapid rate of transmission, is a pandemic that spread across the world, resulting in more than 3,000,000 deaths globally. Currently, several drugs have been used for the clinical treatment of COVID-19, such as antivirals (radecivir, baritinib), monoclonal antibodies (tocilizumab), and glucocorticoids (dexamethasone). Accumulating evidence indicates that long noncoding RNAs (lncRNAs) are essential regulators of virus infections and antiviral immune responses including biological processes that are involved in the regulation of COVID-19 and subsequent disease states. Upon viral infections, cellular lncRNAs directly regulate viral genes and influence viral replication and pathology through virus-mediated changes in the host transcriptome. Additionally, several host lncRNAs could help the occurrence of viral immune escape by inhibiting type I interferons (IFN-1), while others could up-regulate IFN-1 production to play an antiviral role. Consequently, understanding the expression and function of lncRNAs during severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection will provide insights into the development of lncRNA-based methods. In this review, we summarized the current findings of lncRNAs in the regulation of the strong inflammatory response, immune dysfunction and thrombosis induced by SARS-CoV-2 infection, discussed the underlying mechanisms, and highlighted the therapeutic challenges of COVID-19 treatment and its future research directions.

scholarly journals A Panel of Broad-Spectrum Antivirals in Topical Ophthalmic Medications from the Drug Repurposing Approach during and after the Coronavirus Disease 2019 Era

2020 ◽  
Vol 9 (8) ◽  
pp. 2441 ◽  
Author(s):  
Pietro Emanuele Napoli ◽  
Lorenzo Mangoni ◽  
Pietro Gentile ◽  
Mirco Braghiroli ◽  
Maurizio Fossarello
Keyword(s):  
Broad Spectrum ◽  
Viral Infections ◽  
Antiviral Treatment ◽  
Clinical Manifestations ◽  
Treatment Protocol ◽  
Drug Repurposing ◽  
Eye Drops ◽  
Secondary Effects ◽  
Artificial Tears ◽  
Global Concern

The coronavirus disease 2019 (COVID-19) represents a global concern of public health caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Its clinical manifestations are characterized by a heterogeneous group of symptoms and pictures (ranging from asymptomatic to lethal courses). The prevalence of conjunctivitis in patients with COVID-19 is at present controversial. Although it has been reported that only 0.9% developed signs of conjunctivitis, other report indicates that up to 31.6% of hospitalized patients had conjunctivitis. Considering the widespread use of topical ophthalmic medications (e.g., eye drops) by the general population, for various reasons (e.g., artificial tears, anti-glaucoma medications, topical antibiotics, etc.), the existence of their side effects as antiviral action should be investigated in-depth because it could possibly explain the aforementioned controversial data and represent a potential antiviral treatment for SARS-CoV-2 replication/diffusion on the ocular surface. Here, we discuss and elucidate the antiviral side effect of many eye drops and ophthalmic ointments commonly used for others purposes, thus showing that these secondary effects (not to be confused with the ‘adverse effects’) might be of primary importance in a number of viral infections (e.g., those for which there is no validated treatment protocol), according to a drug repurposing approach. Some active ingredients or excipients described here have activity against other types of viruses, thus suggesting potential broad-spectrum applications.

scholarly journals A Novel Agonist of the TRIF Pathway Induces a Cellular State Refractory to Replication of Zika, Chikungunya, and Dengue Viruses

mBio ◽  
2017 ◽  
Vol 8 (3) ◽  
Author(s):  
Kara M. Pryke ◽  
Jinu Abraham ◽  
Tina M. Sali ◽  
Bryan J. Gall ◽  
Iris Archer ◽  
...  
Keyword(s):  
Adaptive Immunity ◽  
Broad Spectrum ◽  
Type I Interferon ◽  
Innate Immune ◽  
Type I ◽  
Emerging Viruses ◽  
Therapeutic Tool ◽  
Viral Pathogens ◽  
Dengue Viruses ◽  
Interferon System

ABSTRACT The ongoing concurrent outbreaks of Zika, Chikungunya, and dengue viruses in Latin America and the Caribbean highlight the need for development of broad-spectrum antiviral treatments. The type I interferon (IFN) system has evolved in vertebrates to generate tissue responses that actively block replication of multiple known and potentially zoonotic viruses. As such, its control and activation through pharmacological agents may represent a novel therapeutic strategy for simultaneously impairing growth of multiple virus types and rendering host populations resistant to virus spread. In light of this strategy’s potential, we undertook a screen to identify novel interferon-activating small molecules. Here, we describe 1-(2-fluorophenyl)-2-(5-isopropyl-1,3,4-thiadiazol-2-yl)-1,2-dihydrochromeno[2,3-c]pyrrole-3,9-dione, which we termed AV-C. Treatment of human cells with AV-C activates innate and interferon-associated responses that strongly inhibit replication of Zika, Chikungunya, and dengue viruses. By utilizing genome editing, we investigated the host proteins essential to AV-C-induced cellular states. This showed that the compound requires a TRIF-dependent signaling cascade that culminates in IFN regulatory factor 3 (IRF3)-dependent expression and secretion of type I interferon to elicit antiviral responses. The other canonical IRF3-terminal adaptor proteins STING and IPS-1/MAVS were dispensable for AV-C-induced phenotypes. However, our work revealed an important inhibitory role for IPS-1/MAVS, but not TRIF, in flavivirus replication, implying that TRIF-directed viral evasion may not occur. Additionally, we show that in response to AV-C, primary human peripheral blood mononuclear cells secrete proinflammatory cytokines that are linked with establishment of adaptive immunity to viral pathogens. Ultimately, synthetic innate immune activators such as AV-C may serve multiple therapeutic purposes, including direct antimicrobial responses and facilitation of pathogen-directed adaptive immunity. IMPORTANCE The type I interferon system is part of the innate immune response that has evolved in vertebrates as a first line of broad-spectrum immunological defense against an unknowable diversity of microbial, especially viral, pathogens. Here, we characterize a novel small molecule that artificially activates this response and in so doing generates a cellular state antagonistic to growth of currently emerging viruses: Zika virus, Chikungunya virus, and dengue virus. We also show that this molecule is capable of eliciting cellular responses that are predictive of establishment of adaptive immunity. As such, this agent may represent a powerful and multipronged therapeutic tool to combat emerging and other viral diseases. IMPORTANCE The type I interferon system is part of the innate immune response that has evolved in vertebrates as a first line of broad-spectrum immunological defense against an unknowable diversity of microbial, especially viral, pathogens. Here, we characterize a novel small molecule that artificially activates this response and in so doing generates a cellular state antagonistic to growth of currently emerging viruses: Zika virus, Chikungunya virus, and dengue virus. We also show that this molecule is capable of eliciting cellular responses that are predictive of establishment of adaptive immunity. As such, this agent may represent a powerful and multipronged therapeutic tool to combat emerging and other viral diseases.

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