scholarly journals Commensal bacteria promote type I interferon signaling to maintain immune tolerance

2021 ◽  
Author(s):  
Adriana Vasquez Ayala ◽  
Kazuhiko Matsuo ◽  
Chia-Yun Hsu ◽  
Marvic Carrillo Terrazas ◽  
Hiutung Chu
Keyword(s):  
Immune Tolerance ◽  
Type I Interferon ◽  
Host Cells ◽  
Type I Interferons ◽  
Type I ◽  
Type I Ifn ◽  
Interferon Signaling ◽  
Mesenteric Lymph Nodes ◽  
Viral Pathogens ◽  
Physiological Processes

Type I interferons (IFN) play essential roles in numerous physiological processes, acting as central coordinators in the host response against pathogens. Upon sensing of microbial ligands, host cells rapidly activate the type I IFN response to prime innate and adaptive immune responses. Recent studies suggest tonic IFN are maintained by commensal microbes and critical in mounting an effective immune response to viral pathogens. Further, emerging developments have extended an immunoregulatory role of type I IFN in the maintenance of immune homeostasis. Yet whether immunomodulatory bacteria from the gut microbiota operate through IFN signaling to promote immune tolerance remains largely unanswered. Here we show that commensal microbes are necessary to maintain type I IFN responses in intestinal tissues. Specifically, Bacteroides fragilis induced type I IFN response in dendritic cells (DCs) and this pathway is necessary for the induction of IL-10-producing Foxp3+ regulatory T cells (Tregs). In addition, we show upregulation of type I IFN related genes in Tregs from mesenteric lymph nodes and colonic lamina propria of mice colonized with B. fragilis. Our findings demonstrate type I interferon signaling plays an important role in microbiota-mediated immune tolerance in the gut.

scholarly journals Hemagglutinin of Influenza A Virus Antagonizes Type I Interferon (IFN) Responses by Inducing Degradation of Type I IFN Receptor 1

2015 ◽  
Vol 90 (5) ◽  
pp. 2403-2417 ◽  
Author(s):  
Chuan Xia ◽  
Madhuvanthi Vijayan ◽  
Curtis J. Pritzl ◽  
Serge Y. Fuchs ◽  
Adrian B. McDermott ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Influenza A Virus ◽  
Influenza A ◽  
Type I Interferon ◽  
Innate Immune ◽  
Host Cells ◽  
Type I ◽  
Type I Ifn ◽  
Type I Ifns ◽  
Ha Protein

ABSTRACTInfluenza A virus (IAV) employs diverse strategies to circumvent type I interferon (IFN) responses, particularly by inhibiting the synthesis of type I IFNs. However, it is poorly understood if and how IAV regulates the type I IFN receptor (IFNAR)-mediated signaling mode. In this study, we demonstrate that IAV induces the degradation of IFNAR subunit 1 (IFNAR1) to attenuate the type I IFN-induced antiviral signaling pathway. Following infection, the level of IFNAR1 protein, but not mRNA, decreased. Indeed, IFNAR1 was phosphorylated and ubiquitinated by IAV infection, which resulted in IFNAR1 elimination. The transiently overexpressed IFNAR1 displayed antiviral activity by inhibiting virus replication. Importantly, the hemagglutinin (HA) protein of IAV was proved to trigger the ubiquitination of IFNAR1, diminishing the levels of IFNAR1. Further, influenza A viral HA1 subunit, but not HA2 subunit, downregulated IFNAR1. However, viral HA-mediated degradation of IFNAR1 was not caused by the endoplasmic reticulum (ER) stress response. IAV HA robustly reduced cellular sensitivity to type I IFNs, suppressing the activation of STAT1/STAT2 and induction of IFN-stimulated antiviral proteins. Taken together, our findings suggest that IAV HA causes IFNAR1 degradation, which in turn helps the virus escape the powerful innate immune system. Thus, the research elucidated an influenza viral mechanism for eluding the IFNAR signaling pathway, which could provide new insights into the interplay between influenza virus and host innate immunity.IMPORTANCEInfluenza A virus (IAV) infection causes significant morbidity and mortality worldwide and remains a major health concern. When triggered by influenza viral infection, host cells produce type I interferon (IFN) to block viral replication. Although IAV was shown to have diverse strategies to evade this powerful, IFN-mediated antiviral response, it is not well-defined if IAV manipulates the IFN receptor-mediated signaling pathway. Here, we uncovered that influenza viral hemagglutinin (HA) protein causes the degradation of type I IFN receptor subunit 1 (IFNAR1). HA promoted phosphorylation and polyubiquitination of IFNAR1, which facilitated the degradation of this receptor. The HA-mediated elimination of IFNAR1 notably decreased the cells' sensitivities to type I IFNs, as demonstrated by the diminished expression of IFN-induced antiviral genes. This discovery could help us understand how IAV regulates the host innate immune response to create an environment optimized for viral survival in host cells.

scholarly journals Dendritic cells require a systemic type I interferon response to mature and induce CD4+ Th1 immunity with poly IC as adjuvant

2009 ◽  
Vol 206 (7) ◽  
pp. 1589-1602 ◽  
Author(s):  
M. Paula Longhi ◽  
Christine Trumpfheller ◽  
Juliana Idoyaga ◽  
Marina Caskey ◽  
Ines Matos ◽  
...  
Keyword(s):  
T Cell ◽  
Type I Interferon ◽  
Host Cells ◽  
Interferon Response ◽  
Type I ◽  
Type I Ifn ◽  
Protein Vaccine ◽  
Adaptive Responses ◽  
Cell Repertoire ◽  
Gag Protein

Relative to several other toll-like receptor (TLR) agonists, we found polyinosinic:polycytidylic acid (poly IC) to be the most effective adjuvant for Th1 CD4+ T cell responses to a dendritic cell (DC)–targeted HIV gag protein vaccine in mice. To identify mechanisms for adjuvant action in the intact animal and the polyclonal T cell repertoire, we found poly IC to be the most effective inducer of type I interferon (IFN), which was produced by DEC-205+ DCs, monocytes, and stromal cells. Antibody blocking or deletion of type I IFN receptor showed that IFN was essential for DC maturation and development of CD4+ immunity. The IFN-AR receptor was directly required for DCs to respond to poly IC. STAT 1 was also essential, in keeping with the type I IFN requirement, but not type II IFN or IL-12 p40. Induction of type I IFN was mda5 dependent, but DCs additionally used TLR3. In bone marrow chimeras, radioresistant and, likely, nonhematopoietic cells were the main source of IFN, but mda5 was required in both marrow–derived and radioresistant host cells for adaptive responses. Therefore, the adjuvant action of poly IC requires a widespread innate type I IFN response that directly links antigen presentation by DCs to adaptive immunity.

scholarly journals Suppression of Type I Interferon Signaling by Flavivirus NS5

Viruses ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 712 ◽  
Author(s):  
Stephanie Thurmond ◽  
Boxiao Wang ◽  
Jikui Song ◽  
Rong Hai
Keyword(s):  
Host Defense ◽  
Type I Interferon ◽  
Mammalian Host ◽  
Type I ◽  
Signal Transducer ◽  
Type I Ifn ◽  
Interferon Signaling ◽  
Structural Protein ◽  
First Line

Type I interferon (IFN-I) is the first line of mammalian host defense against viral infection. To counteract this, the flaviviruses, like other viruses, have encoded a variety of antagonists, and use a multi-layered molecular defense strategy to establish their infections. Among the most potent antagonists is non-structural protein 5 (NS5), which has been shown for all disease-causing flaviviruses to target different steps and players of the type I IFN signaling pathway. Here, we summarize the type I IFN antagonist mechanisms used by flaviviruses with a focus on the role of NS5 in regulating one key regulator of type I IFN, signal transducer and activator of transcription 2 (STAT2).

scholarly journals Conidia but Not Yeast Cells of the Fungal Pathogen Histoplasma capsulatum Trigger a Type I Interferon Innate Immune Response in Murine Macrophages

2010 ◽  
Vol 78 (9) ◽  
pp. 3871-3882 ◽  
Author(s):  
Diane O. Inglis ◽  
Charlotte A. Berkes ◽  
Davina R. Hocking Murray ◽  
Anita Sil
Keyword(s):  
Histoplasma Capsulatum ◽  
Type I Interferon ◽  
Respiratory Infections ◽  
Host Cells ◽  
Yeast Cells ◽  
Host Immune System ◽  
Type I ◽  
Type I Ifn ◽  
Murine Bone Marrow ◽  
Reverse Transcription Pcr

ABSTRACT Histoplasma capsulatum is the most common cause of fungal respiratory infections and can lead to progressive disseminated infections, particularly in immunocompromised patients. Infection occurs upon inhalation of the aerosolized spores, known as conidia. Once inside the host, conidia are phagocytosed by alveolar macrophages. The conidia subsequently germinate and produce a budding yeast-like form that colonizes host macrophages and can disseminate throughout host organs and tissues. Even though conidia are the predominant infectious particle for H. capsulatum and are the first cell type encountered by the host during infection, very little is known at a molecular level about conidia or about their interaction with cells of the host immune system. We examined the interaction between conidia and host cells in a murine bone-marrow-derived macrophage model of infection. We used whole-genome expression profiling and quantitative reverse transcription-PCR (qRT-PCR) to monitor the macrophage signaling pathways that are modulated during infection with conidia. Our analysis revealed that type I interferon (IFN)-responsive genes and the beta type I IFN (IFN-β) were induced in macrophages during infection with H. capsulatum conidia but not H. capsulatum yeast cells. Further analysis revealed that the type I IFN signature induced in macrophages in response to conidia is independent of Toll-like receptor (TLR) signaling and the cytosolic RNA sensor MAVS but is dependent on the transcription factor interferon regulatory factor 3 (IRF3). Interestingly, H. capsulatum growth was restricted in mice lacking the type I IFN receptor, indicating that an intact host type I IFN response is required for full virulence of H. capsulatum in mice.

scholarly journals Type I interferons link skin-associated dysbiotic commensal bacteria to pathogenic inflammation and angiogenesis in rosacea

2021 ◽  
Author(s):  
Alessio Mylonas ◽  
Heike Hawerkamp ◽  
Yichen Wang ◽  
Olivier Demaria ◽  
Stephan Meller ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Type I Interferon ◽  
Plasmacytoid Dendritic Cells ◽  
Commensal Bacteria ◽  
Host Cells ◽  
Type I Interferons ◽  
Type I ◽  
Interferon Production ◽  
Microbial Dysbiosis ◽  
Fluctuating Course

Abstract Rosacea is a common chronic inflammatory skin disease that is characterized by a fluctuating course of excessive inflammation and apparent neovascularization. Microbial dysbiosis with high density of B. oleronius and increased activity of the serine protease kallikrein 5, which cleaves cathelicidin antimicrobial peptide, have been recognized as key pathogenic triggers in rosacea. However, how these events are linked to the hallmarks of the disease remains unknown. Here, we show that type I interferons produced by plasmacytoid dendritic cells represent the pivotal link between dysbiosis, an aberrant immune response, and neovascularization in rosacea. In fact, compared to other commensal bacteria, B. oleronius is highly susceptible and preferentially killed by cathelicidin antimicrobial peptides leading to enhanced generation of complexes with DNA. DNA from skin-associated microbiota but not from host cells is required for cathelicidin-induced activation of plasmacytoid dendritic cells and type I-interferon production, which is further amplified by B. oleronius. Moreover, kallikrein 5 cleaves cathelicidin into peptides with heightened DNA binding and type I interferon-inducing capacities, further facilitating type I interferon production within the skin. In turn, type I interferons induce IL22 whilst simultaneously rendering endothelial cells responsive through upregulation of the IL22-receptor, and thereby driving drive neoangiogenesis. These findings unravel novel pathomechanisms, which directly link several hallmarks of rosacea to the killing of dysbiotic commensal bacteria and the induction of a pathogenic type-I interferon-TH17/22 pathway.

scholarly journals Identification of Natural Molecular Determinants of Ross River Virus Type I Interferon Modulation

2020 ◽  
Vol 94 (8) ◽  
Author(s):  
Xiang Liu ◽  
Margit Mutso ◽  
Liubov Cherkashchenko ◽  
Eva Zusinaite ◽  
Lara J. Herrero ◽  
...  
Keyword(s):  
Amino Acid ◽  
Type I Interferon ◽  
Nonstructural Protein ◽  
Site Directed Mutagenesis ◽  
Type I Interferons ◽  
Ross River Virus ◽  
Type I ◽  
Type I Ifn ◽  
Nonstructural Protein 1

ABSTRACT Ross River virus (RRV) belongs to the genus Alphavirus and is prevalent in Australia. RRV infection can cause arthritic symptoms in patients and may include rash, fever, arthralgia, and myalgia. Type I interferons (IFN) are the primary antiviral cytokines and trigger activation of the host innate immune system to suppress the replication of invading viruses. Alphaviruses are able to subvert the type I IFN system, but the mechanisms used are ill defined. In this study, seven RRV field strains were analyzed for induction of and sensitivity to type I IFN. The sensitivities of these strains to human IFN-β varied significantly and were highest for the RRV 2548 strain. Compared to prototype laboratory strain RRV-T48, RRV 2548 also induced higher type I IFN levels both in vitro and in vivo and caused milder disease. To identify the determinants involved in type I IFN modulation, the region encoding the nonstructural proteins (nsPs) of RRV 2548 was sequenced, and 42 amino acid differences from RRV-T48 were identified. Using fragment swapping and site-directed mutagenesis, we discovered that substitutions E402A and R522Q in nsP1 as well as Q619R in nsP2 were responsible for increased sensitivity of RRV 2548 to type I IFN. In contrast, substitutions A31T, N219T, S580L, and Q619R in nsP2 led to induction of higher levels of type I IFN. With exception of E402A, all these variations are common for naturally occurring RRV strains. However, they are different from all known determinants of type I IFN modulation reported previously in nsPs of alphaviruses. IMPORTANCE By identifying natural Ross River virus (RRV) amino acid determinants for type I interferon (IFN) modulation, this study gives further insight into the mechanism of type I IFN modulation by alphaviruses. Here, the crucial role of type I IFN in the early stages of RRV disease pathogenesis is further demonstrated. This study also provides a comparison of the roles of different parts of the RRV nonstructural region in type I IFN modulation, highlighting the importance of nonstructural protein 1 (nsP1) and nsP2 in this process. Three substitutions in nsP1 and nsP2 were found to be independently associated with enhanced type I IFN sensitivity, and four independent substitutions in nsP2 were important in elevated type I IFN induction. Such evidence has clear implications for RRV immunobiology, persistence, and pathology. The identification of viral proteins that modulate type I IFN may also have importance for the pathogenesis of other alphaviruses.

Distinct Roles of Type I and Type III Interferons During a Native Murine β Coronavirus Lung Infection

2021 ◽  
Author(s):  
Lokesh Sharma ◽  
Xiaohua Peng ◽  
Hua Qing ◽  
Brandon K. Hilliard ◽  
Jooyoung Kim ◽  
...  
Keyword(s):  
Type I Interferon ◽  
Lung Infection ◽  
Viral Clearance ◽  
Type I Interferons ◽  
Type I ◽  
Interferon Signaling ◽  
Type Iii ◽  
Coronavirus Infection ◽  
Type Iii Interferon

Coronaviruses are a major healthcare threat to humankind. Currently, the host factors that contribute to limit disease severity in healthy young patients are not well defined. Interferons are key antiviral molecules, especially type I and type III interferons. The role of these interferons during coronavirus disease is a subject of debate. Here using mice that are deficient in type I (IFNAR1 -/- ), type III (IFNLR1 -/- ) or both (IFNAR1/LR1 -/- ) interferon signaling pathways and murine adapted coronavirus (MHV-A59) administered through intranasal route, we define the role of interferons in coronavirus infection. We show that type I interferons play a major role in host survival in this model while a minimal role of type III interferons was manifested only in the absence of type I interferons or during a lethal dose of coronavirus. IFNAR1 -/- and IFNAR1/LR1 -/- mice had an uncontrolled viral burden in the airways and lung and increased viral dissemination to other organs. The absence of only type III interferon signaling had no measurable difference in the viral load. The increased viral load in IFNAR1 -/- and IFNAR1/LR1 -/- mice was associated with increased tissue injury, especially evident in the lung and liver. Type I but not type III interferon treatment was able to promote survival if treated during early disease. Further, we show that type I interferon signaling in macrophages contributes to the beneficial effects during coronavirus infection in mice. Importance: The antiviral and pathological potential of type I and type III interferons during coronavirus infection remains poorly defined and opposite findings have been reported. We report that both type I and type III interferons have anti-coronaviral activities, but their potency and organ specificity differ. Type I interferons deficiency rendered the mice susceptible to even a sublethal murine coronavirus infection, while the type III interferon deficiency impaired survival only during a lethal infection or during a sublethal infection in absence of type I interferon signaling. While treatment with both type I and III interferons promoted viral clearance in the airways and lung, only type I interferons promoted the viral clearance in the liver and improved host survival upon early treatment (12 hours post infection). This study demonstrates distinct roles and potency of type I and type III interferons and their therapeutic potential during coronavirus lung infection.

scholarly journals HDAC11 regulates type I interferon signaling through defatty-acylation of SHMT2

2019 ◽  
Vol 116 (12) ◽  
pp. 5487-5492 ◽  
Author(s):  
Ji Cao ◽  
Lei Sun ◽  
Pornpun Aramsangtienchai ◽  
Nicole A. Spiegelman ◽  
Xiaoyu Zhang ◽  
...  
Keyword(s):  
Immune Responses ◽  
Type I Interferon ◽  
Type I ◽  
Type I Ifn ◽  
Interferon Signaling ◽  
Surface Level ◽  
Fatty Acylation ◽  
Cell Surface Level ◽  
Specific Inhibitors ◽  
Class Iv

The smallest histone deacetylase (HDAC) and the only class IV HDAC member, HDAC11, is reported to regulate immune activation and tumorigenesis, yet its biochemical function is largely unknown. Here we identify HDAC11 as an efficient lysine defatty-acylase that is >10,000-fold more efficient than its deacetylase activity. Through proteomics studies, we hypothesized and later biochemically validated SHMT2 as a defatty-acylation substrate of HDAC11. HDAC11-catalyzed defatty-acylation did not affect the enzymatic activity of SHMT2. Instead, it affects the ability of SHMT2 to regulate type I IFN receptor ubiquitination and cell surface level. Correspondingly, HDAC11 depletion increased type I IFN signaling in both cell culture and mice. This study not only demonstrates that HDAC11 has an activity that is much more efficient than the corresponding deacetylase activity, but also expands the physiological functions of HDAC11 and protein lysine fatty acylation, which opens up opportunities to develop HDAC11-specific inhibitors as therapeutics to modulate immune responses.

scholarly journals Manipulation of Type I Interferon Signaling by HIV and AIDS-Associated Viruses

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Buyuan He ◽  
James T. Tran ◽  
David Jesse Sanchez
Keyword(s):  
Viral Infections ◽  
Type I Interferon ◽  
Antiviral Effect ◽  
Hiv And Aids ◽  
Type I Interferons ◽  
Type I ◽  
Interferon Signaling ◽  
Chronic Viral Infections ◽  
Pathogenic Viruses ◽  
The Impact

Type I Interferons were first described for their profound antiviral abilities in cell culture and animal models, and later, they were translated into potent antiviral therapeutics. However, as additional studies into the function of Type I Interferons progressed, it was also seen that pathogenic viruses have coevolved to encode potent mechanisms allowing them to evade or suppress the impact of Type I Interferons on their replication. For chronic viral infections, such as HIV and many of the AIDS-associated viruses, including HTLV, HCV, KSHV, and EBV, the clinical efficacy of Type I Interferons is limited by these mechanisms. Here, we review some of the ways that HIV and AIDS-associated viruses thrive in Type I Interferon-rich environments via mechanisms that block the function of this important antiviral cytokine. Overall, a better understanding of these mechanisms creates avenues to better understand the innate immune response to these viruses as well as plan the development of antivirals that would allow the natural antiviral effect of Type I Interferons to manifest during these infections.

Sign in / Sign up

Export Citation Format

Share Document