Pseudorabies virus inhibits type I and type III interferon-induced signaling via proteasomal degradation of Janus kinases

2021 ◽  
Author(s):  
Yue Yin ◽  
Nicolás Romero ◽  
Herman W. Favoreel

Both type I and III interferons (IFNs) play a crucial role in host antiviral response by activating the JAK/STAT (Janus kinase/signal transducer and activator of transcription) signaling pathway to trigger the expression of antiviral IFN-stimulated genes (ISGs). We report that the porcine alphaherpesvirus pseudorabies virus (PRV) triggers proteasomal degradation of the key Janus kinases Jak1 and to a lesser exent Tyk2, thereby inhibiting both type I and III IFN-induced STAT1 phosphorylation and suppressing IFN-induced expression of ISGs. UV-inactivated PRV did not interfere with IFN signaling. In addition, deletion of the EP0 gene from the PRV genome or inhibition of viral genome replication did not affect PRV-induced inhibition of IFN signaling. To our knowledge, this is the first report describing Janus kinase degradation by alphaherpesviruses. These findings thus reveal a novel alphaherpesvirus evasion mechanism of type I and type III IFNs. IMPORTANCE Type I and III IFNs trigger signaling via Janus kinases that phosphorylate and activate STAT transcription factors, leading to the expression of antiviral interferon-stimulated genes (ISGs) that result in an antiviral state of host cells. Viruses have evolved various mechanisms to evade this response. Our results indicate that an alphaherpesvirus, the porcine pseudorabies virus (PRV), inhibits both type I and III IFNs signaling pathways by triggering proteasome-dependent degradation of the key Janus kinases Jak1 and Tyk2 and consequent inhibition of STAT1 phosphorylation and suppression of ISG expression. Moreover, we found that this inhibition is not caused by incoming virions and does not depend on expression of the viral EP0 protein or viral true late proteins. These data for the first time address alphaherpesvirus evasion of type III IFN-mediated signaling and reveal a previously uncharacterized alphaherpesvirus mechanism of IFN evasion via proteasomal degradation of Janus kinases.

2020 ◽  
Vol 295 (41) ◽  
pp. 13958-13964 ◽  
Author(s):  
Ulrike Felgenhauer ◽  
Andreas Schoen ◽  
Hans Henrik Gad ◽  
Rune Hartmann ◽  
Andreas R. Schaubmar ◽  
...  

The recently emerged severe acute respiratory syndrome coronavirus-2 (SARS–CoV-2) is the causative agent of the devastating COVID-19 lung disease pandemic. Here, we tested the inhibitory activities of the antiviral interferons of type I (IFN-α) and type III (IFN-λ) against SARS–CoV-2 and compared them with those against SARS–CoV-1, which emerged in 2003. Using two mammalian epithelial cell lines (human Calu-3 and simian Vero E6), we found that both IFNs dose-dependently inhibit SARS–CoV-2. In contrast, SARS–CoV-1 was restricted only by IFN-α in these cell lines. SARS–CoV-2 generally exhibited a broader IFN sensitivity than SARS–CoV-1. Moreover, ruxolitinib, an inhibitor of IFN-triggered Janus kinase/signal transducer and activator of transcription signaling, boosted SARS–CoV-2 replication in the IFN-competent Calu-3 cells. We conclude that SARS–CoV-2 is sensitive to exogenously added IFNs. This finding suggests that type I and especially the less adverse effect–prone type III IFN are good candidates for the management of COVID-19.


Microbiology ◽  
2014 ◽  
Vol 160 (7) ◽  
pp. 1417-1426 ◽  
Author(s):  
Dennis Neeld ◽  
Yongxin Jin ◽  
Candace Bichsel ◽  
Jinghua Jia ◽  
Jianhui Guo ◽  
...  

Pseudomonas aeruginosa is a Gram-negative opportunistic human pathogen possessing a type III secretion system (T3SS) which injects toxic effector proteins into mammalian host cells. In previous studies, P. aeruginosa strains lacking all of the known type III effectors were shown to cause cytotoxicity upon prolonged infection time. In this study, we report the identification of a new cytotoxin, nucleoside diphosphate kinase (NDK), which is injected into eukaryotic cells in a T3SS-dependent manner. Injection of NDK is inhibited by the presence of previously known effectors of the T3SS, with an effectorless strain injecting the highest amount, suggesting active competition with the known T3SS effectors. NDK is shown to cause a cytotoxic response when expressed in eukaryotic cells, and P. aeruginosa strains harbouring NDK also show a greater toxicity than strains lacking it. Interestingly, the cytotoxic effect of intracellular NDK is independent of its kinase activity. In previous studies, NDK was shown to be secreted into culture supernatants via a type I secretion system and cause cytotoxicity in a kinase-dependent manner. Therefore, the current study highlights an alternative route of NDK secretion as well as two different cytotoxic mechanisms of NDK, depending on the extra- or intra-cellular location of the protein.


mBio ◽  
2018 ◽  
Vol 9 (3) ◽  
Author(s):  
Matthew A. Szaniawski ◽  
Adam M. Spivak ◽  
James E. Cox ◽  
Jonathan L. Catrow ◽  
Timothy Hanley ◽  
...  

ABSTRACTMacrophages are susceptible to human immunodeficiency virus type 1 (HIV-1) infection despite abundant expression of antiviral proteins. Perhaps the most important antiviral protein is the restriction factor sterile alpha motif domain and histidine/aspartic acid domain-containing protein 1 (SAMHD1). We investigated the role of SAMHD1 and its phospho-dependent regulation in the context of HIV-1 infection in primary human monocyte-derived macrophages and the ability of various interferons (IFNs) and pharmacologic agents to modulate SAMHD1. Here we show that stimulation by type I, type II, and to a lesser degree, type III interferons share activation of SAMHD1 via dephosphorylation at threonine-592 as a consequence of signaling. Cyclin-dependent kinase 1 (CDK1), a known effector kinase for SAMHD1, was downregulated at the protein level by all IFN types tested. Pharmacologic inhibition or small interfering RNA (siRNA)-mediated knockdown of CDK1 phenocopied the effects of IFN on SAMHD1. A panel of FDA-approved tyrosine kinase inhibitors potently induced activation of SAMHD1 and subsequent HIV-1 inhibition. The viral restriction imposed via IFNs or dasatinib could be overcome through depletion of SAMHD1, indicating that their effects are exerted primarily through this pathway. Our results demonstrate that SAMHD1 activation, but not transcriptional upregulation or protein induction, is the predominant mechanism of HIV-1 restriction induced by type I, type II, and type III IFN signaling in macrophages. Furthermore, SAMHD1 activation presents a pharmacologically actionable target through which HIV-1 infection can be subverted.IMPORTANCEOur experimental results demonstrate that SAMHD1 dephosphorylation at threonine-592 represents a central mechanism of HIV-1 restriction that is common to the three known families of IFNs. While IFN types I and II were potent inhibitors of HIV-1, type III IFN showed modest to undetectable activity. Regulation of SAMHD1 by IFNs involved changes in phosphorylation status but not in protein levels. Phosphorylation of SAMHD1 in macrophages occurred at least in part via CDK1. Tyrosine kinase inhibitors similarly induced SAMHD1 dephosphorylation, which protects macrophages from HIV-1 in a SAMHD1-dependent manner. SAMHD1 is a critical restriction factor regulating HIV-1 infection of macrophages.


2005 ◽  
Vol 86 (6) ◽  
pp. 1589-1596 ◽  
Author(s):  
Nathan W. Bartlett ◽  
Karen Buttigieg ◽  
Sergei V. Kotenko ◽  
Geoffrey L. Smith

Human interferon lambdas (IFN-λs) (type III IFNs) exhibit antiviral activity in vitro by binding to a receptor complex distinct from that used by type I and type II IFNs, and subsequent signalling through the Janus kinase signal transducers and activators of transcription (STAT) pathway. However, evidence for a function of type III IFNs during virus infection in vivo is lacking. Here, the expression of murine IFN-λs by recombinant vaccinia virus (VACV) is described and these proteins are shown to have potent antiviral activity in vivo. VACV expressing murine IFN-λ2 (vIFN-λ2) and IFN-λ3 (vIFN-λ3) showed normal growth in tissue culture and expressed N-glycosylated IFN-λ in infected cell extracts and culture supernatants. The role that murine IFN-λs play during virus infection was assessed in two different mouse models. vIFN-λ2 and vIFN-λ3 were avirulent for mice infected intranasally and induced no signs of illness or weight loss, in contrast to control viruses. Attenuation of vIFN-λ2 was associated with increases in lymphocytes in bronchial alveolar lavages and CD4+ T cells in total-lung lymphocyte preparations. In addition, vIFN-λ2 was cleared more rapidly from infected lungs and, in contrast to control viruses, did not disseminate to the brain. Expression of IFN-λ2 also attenuated VACV in an intradermal-infection model, characterized by a delay in lesion onset and reduced lesion size. Thus, by characterizing murine IFN-λs within a mouse infection model, the potent antiviral and immunostimulatory activity of IFN-λs in response to poxvirus infection has been demonstrated.


2014 ◽  
Vol 82 (5) ◽  
pp. 2059-2067 ◽  
Author(s):  
Sabriya A. Stukes ◽  
Hillel W. Cohen ◽  
Arturo Casadevall

ABSTRACTCryptococcus neoformansis a facultative intracellular pathogen and the causative agent of cryptococcosis, a disease that is often fatal to those with compromised immune systems.C. neoformanshas the capacity to escape phagocytic cells through a process known as nonlytic exocytosis whereby the cryptococcal cell is released from the macrophage into the extracellular environment, leaving both the host and pathogen alive. Little is known about the mechanism behind nonlytic exocytosis, but there is evidence that both the fungal and host cells contribute to the process. In this study, we used time-lapse movies ofC. neoformans-infected macrophages to delineate the kinetics and quantitative aspects of nonlytic exocytosis. We analyzed approximately 800 macrophages containing intracellularC. neoformansand identified 163 nonlytic exocytosis events that were further characterized into three subcategories: type I (complete emptying of macrophage), type II (partial emptying of macrophage), and type III (cell-to-cell transfer). The majority of type I and II events occurred after several hours of intracellular residence, whereas type III events occurred significantly (P< 0.001) earlier in the course of macrophage infection. Our results show that nonlytic exocytosis is a morphologically and temporally diverse process that occurs relatively rapidly in the course of macrophage infection.


2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S34-S35
Author(s):  
John V Williams ◽  
Yu Zhang ◽  
Jiuyang Xu ◽  
Margot Miranda-Katz ◽  
Helen Rich ◽  
...  

Abstract Background Human metapneumovirus (HMPV) is a leading cause of respiratory tract infection in children and adults. However, mechanisms of pathogenesis are not fully understood. Methods We tested HMPV clinical and laboratory isolates in an established C57BL/6 mouse model and measured weight loss, airway function, and viral titers. Immune responses were determined using cytokine quantitation and flow cytometry. Results HMPV clinical isolates induced variable disease severity ranging from mild to fatal disease. Laboratory strain TN/94-49 did not cause weight loss, but mice infected with clinical isolate C2-202 showed dramatic weight loss and 40% mortality within 5 days post-infection (Figure 1). These findings were confirmed in other inbred mouse strains. C2-202-infected mice also suffered from impaired pulmonary function post-recovery. Lung viral titer did not correlate with disease severity, suggesting immune-mediated pathogenesis. C2-202-infected mice exhibited increased production of type I and III interferons (IFN) and pro-inflammatory cytokines, and lung neutrophil infiltration. However, neutrophil depletion or inflammasome inactivation did not reduce disease. Stat1/Stat2 double knockout (KO) mice lacking type I and III IFN signaling exhibited reduced weight loss but increased lung viral titer after C2-202 infection (Figure 2). Type I IFN receptor (IFNAR) KO mice infected with C2-202 had reduced weight loss but unchanged lung viral titer (Figure 3), while the addition of type III IFN blockade to C2-202-infected IFNAR mice had no effect on disease but increased lung viral titer (Figure 4). Conclusion These results suggest that severe disease caused by virulent HMPV was due to exuberant IFN response. Moreover, type I IFN was primarily associated with disease, while type III IFN was associated with viral clearance. These data suggest that IFN signaling plays an important role in HMPV pathogenesis, and thus serves as a potential therapeutic target. Disclosures All Authors: No reported Disclosures.


2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Rebecca Mahony ◽  
Lindsay Broadbent ◽  
Jacen S. Maier-Moore ◽  
Ultan F. Power ◽  
Caroline A. Jefferies

Cytokine ◽  
2012 ◽  
Vol 59 (3) ◽  
pp. 562-563
Author(s):  
T. Mahlakoiv ◽  
D. Ritz ◽  
L. Enjuanes ◽  
M.A. Müller ◽  
C. Drosten ◽  
...  

Viruses ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 405
Author(s):  
Yingying Li ◽  
Ling Zhao ◽  
Zhaochen Luo ◽  
Yachun Zhang ◽  
Lei Lv ◽  
...  

Rabies, caused by rabies virus (RABV), is a fatal neurological disease that still causes more than 59,000 human deaths each year. Type III interferon IFN-λs are cytokines with type I IFN-like antiviral activities. Although IFN-λ can restrict the infection for some viruses, especially intestinal viruses, the inhibitory effect against RABV infection remains undefined. In this study, the function of type III IFN against RABV infection was investigated. Initially, we found that IFN-λ2 and IFN-λ3 could inhibit RABV replication in cells. To characterize the role of IFN-λ in RABV infection in a mouse model, recombinant RABVs expressing murine IFN-λ2 or IFN-λ3, termed as rB2c-IFNλ2 or rB2c-IFNλ3, respectively, were constructed and rescued. It was found that expression of IFN-λ could reduce the pathogenicity of RABV and limit viral spread in the brains by different infection routes. Furthermore, expression of IFN-λ could induce the activation of the JAK-STAT pathway, resulting in the production of interferon-stimulated genes (ISGs). It was also found that rRABVs expressing IFN-λ could reduce the production of inflammatory cytokines in primary astrocytes and microgila cells, restrict the opening of the blood-brain barrier (BBB), and prevent excessive infiltration of inflammatory cells into the brain, which could be responsible for the neuronal damage caused by RABV. Consistently, IFN-λ was found to maintain the integrity of tight junction (TJ) protein ZO-1 of BBB to alleviate neuroinflammation in a transwell model. Our study underscores the role of IFN-λ in inhibiting RABV infection, which potentiates IFN-λ as a possible therapeutic agent for the treatment of RABV infection.


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