The innate immune response is the first line of defense for the host against viral infections. Targeted degradation of pathogenic microorganisms through autophagy, in conjunction with pattern recognition receptors synergistically inducing the production of interferon (IFN), constitutes an important pathway for the body to resist viral infections. Rubicon, a Run domain Beclin 1-interacting and cysteine-rich domain protein, has an inhibitory effect on autophagy and IFN production. On the one hand, Rubicon, as a component of the phosphoinositide 3-kinase (PI3K) complex, interacts with different domains of vacuolar protein sorting 34 (Vps34), ultraviolet radiation resistance associated gene (UVRAG), guanosine triphosphate (GTP) kinase, and RAS oncogene family member 7 (Rab7) to mediate the inhibition of autophagy maturation; on the other hand, Rubicon inhibits the ubiquitination of nuclear factor κB essential modulator (NEMO) and the dimerization of interferon regulatory factor 3 (IRF3), thereby blocking the signal transduction related to IFN production. Research has revealed that various viruses, such as Kaposi's sarcoma-associated herpesvirus (KSHV), hepatitis B virus (HBV), Sendai virus (SeV), and hepatitis C virus (HCV), achieve innate immune evasion by regulating the expression or function of Rubicon. Rubicon is expected to be a new target for antiviral therapy.
Humans ; Autophagy/immunology* ; Immunity, Innate ; Interferons/immunology* ; Immune Evasion ; Animals ; Virus Diseases/virology* ; Signal Transduction ; Viruses/immunology* ; Intracellular Signaling Peptides and Proteins/immunology* ; Autophagy-Related Proteins

Bluetongue virus (BTV) usually infects sheep, cattle, deer and other domesticated and wild ruminants through the bite of the vector insects, Culicoide, causing bluetongue (BT). BT in subtropical and even temperate regions poses a serious threat to the development and international trade of the livestock industry. This article introduced the structure and cellular invasion, and summarized the mechanisms of anti-BTV immune response of host cells and antagonism of host cell innate immune response by the non-structural proteins (e.g., NS3 and NS4) and structural proteins (e.g., VP3 and VP4) of BTV. This review provided a basis for understanding the antagonism mechanisms of BTV against the interferon (IFN) immune response in the host cell and the pathogenesis of BTV as well as for developing novel vaccines against this virus.
Bluetongue virus/immunology* ; Animals ; Bluetongue/prevention & control* ; Immunity, Innate ; Interferons/immunology* ; Sheep ; Viral Nonstructural Proteins/immunology* ; Cattle

Porcine epidemic diarrhea virus (PEDV) is a highly infectious pathogen that can cause severe diseases in pigs and result in enormous economic losses in the worldwide swine industry. Previous studies revealed that PEDV exhibits an obvious capacity for modulating interferon (IFN) signaling or expression. The newly discovered type III IFN, which plays a crucial role in antiviral immunity, has strong antiviral activity against PEDV proliferation in IPEC-J2 cells. In this study, we aimed to investigate the effect of PEDV nucleocapsid (N) protein on type III IFN-λ. We found that the N proteins of ten PEDV strains isolated between 2013 and 2017 from different local farms shared high nucleotide identities, while the N protein of the CV777 vaccine strain formed a monophyletic branch in the phylogenetic tree. The N protein of the epidemic strain could antagonize type III IFN, but not type I or type II IFN expression induced by polyinosinic-polycytidylic acid (poly(I:C)) in IPEC-J2 cells. Subsequently, we demonstrated that the inhibition of poly(I:C)-induced IFN-λ3 production by PEDV N protein was dependent on the blocking of nuclear factor-κB (NF-κB) nuclear translocation. These findings might help increase understanding of the pathogenesis of PEDV and its mechanisms for evading the host immune response.
Active Transport, Cell Nucleus ; Animals ; Coronavirus Infections ; immunology ; veterinary ; virology ; Genes, Viral ; Host-Pathogen Interactions ; immunology ; Interferons ; antagonists & inhibitors ; biosynthesis ; genetics ; Interleukins ; antagonists & inhibitors ; biosynthesis ; genetics ; NF-kappa B ; metabolism ; Nucleocapsid Proteins ; genetics ; immunology ; physiology ; Porcine epidemic diarrhea virus ; genetics ; pathogenicity ; physiology ; Promoter Regions, Genetic ; Swine ; Swine Diseases ; immunology ; virology

Animals ; Humans ; Immunity, Innate ; immunology ; Influenza, Human ; immunology ; Interferons ; immunology ; Orthomyxoviridae Infections ; immunology ; virology

Interferon-induced Transmembrane Proteins (IFITMs) were identified through small interference RNA (siRNA) screening method in 1980s. The antiviral properties of the IFITMs were firstly discovered in 1996. Recently, its antiviral effect and mechanism have become a research hotspot. Many studies have shown that IFITM can inhibit the replication of multiple pathogenic viruses, including influenza A virus (IAV), Human Immunodeficiency Virus (HIV-1), hepatitis C virus (HCV), Ebola virus (EBOV), West Nile virus and so on. IFITMs inhibit the replication of virus in the early stage of the viral life cycle, which occurred before the release of viral genomes into the cytosol. Recent studies indicate that IFITM proteins could block viral replication by mediate viral membrane fusion. However, the mechanism is still under investigation. Here we review the discovery and characterization of the IFITM proteins, elucidate their antiviral activities and the potential mechanisms.
Animals ; Humans ; Interferons ; genetics ; immunology ; Membrane Proteins ; genetics ; immunology ; Virus Diseases ; genetics ; immunology ; virology ; Viruses ; genetics ; immunology

Animals ; B7-H1 Antigen ; immunology ; Cell Line, Tumor ; Gene Expression Regulation, Neoplastic ; immunology ; Humans ; Interferons ; immunology ; Mice ; Neoplasm Proteins ; immunology ; Neoplasms ; immunology ; Up-Regulation ; immunology

Influenza A virus can create acute respiratory infection in humans and animals throughout the world, and it is still one of the major causes of morbidity and mortality in humans worldwide. Numerous studies have shown that influenza A virus infection induces rapidly host innate immune response. Influenza A virus triggers the activation of signaling pathways that are dependent on host pattern recognition receptors (PRRs) including toll like receptors (TLRs) and RIG-I like receptors (RLRs). Using a variety of regulatory mechanisms, these signaling pathways activate downstream transcript factors that control expression of various interferons and cytokines, such as type I and type III interferons. Thus, these interferons stimulate the transcript of relevant interferon-stimulated genes (ISGs) and expression of the antiviral proteins, which are critical components of host innate immunity. In this review, we will highlight the mechanisms by which influenza A virus infection induces the interferon-mediated host innate immunity.
Cytokines ; immunology ; DEAD Box Protein 58 ; DEAD-box RNA Helicases ; immunology ; Humans ; Immunity, Innate ; Influenza A virus ; Influenza, Human ; immunology ; Interferons ; immunology ; Receptors, Pattern Recognition ; immunology ; Signal Transduction ; Toll-Like Receptors ; immunology

Interferon response is the first line of host defense against virus infection. Recent years have witnessed tremendous progress in understanding of fish innate response to virus infection, especially in fish interferon antiviral response. A line of fish genes involved in interferon antiviral response have been identified and functional studies further reveal that fish possess an IFN antiviral system similar to mammals. However, fish virus-induced interferon genes contain introns similar to mammalian type III interferon genes although they encode proteins similar to type I interferons, which makes it hard to understand the evolution of vertebrate interferon genes directly resulting in a debate on nomenclature of fish interferon genes. Actually, fish display some unique mechanisms underlying interferon antiviral response. This review documents the recent progress on fish interferon response and its molecular mechanism.
Animals ; Fish Diseases ; immunology ; virology ; Fish Proteins ; genetics ; metabolism ; Fishes ; immunology ; virology ; Gene Expression Regulation ; Interferons ; genetics ; immunology ; STAT1 Transcription Factor ; metabolism ; Virus Diseases ; immunology ; veterinary

BACKGROUND: Atopic dermatitis (AD) is a chronic inflammation of the skin that often appears in early childhood. The manifestation is related to the tendency towards T helper 2 cytokine immune responses (interleukin (IL)-4, IL-5). Genetic factors are suggested to play important roles in AD, and it can be transmitted to newborns, increasing their risk of developing allergies. OBJECTIVE: To determine the association between cord-blood cytokine levels (IL-5, interferon (IFN) γ), cord-blood total immunoglobulin E (IgE) level, perinatal environmental exposure, and the risks of allergy as well as the development of AD in the first 6 months of life. METHODS: A 6-month cohort study with a nested case-control within was conducted on newborns in Jakarta from December 2008 until May 2009. After the umbilical cord blood samples were taken and stored, subjects were followed up monthly until 6 months old. The occurrence of AD and lifestyle or environmental exposures were recorded. The allergic risk was determined using a modified pediatric allergy immunology work groups scoring system based on allergic history (allergic rhinitis, asthma, AD) in the family. The levels of IL-5 and IFN-γ were measured using ELISA and total IgE by CAP system FEIA. Multivariate analysis was used to evaluate risk factors. RESULTS: This study was conducted on 226 subjects. The incidence of AD was 16.4%; of those, 59% had low risk allergy, 38.5% moderate, and 2% high risk. AD mostly occurred at the age of 1 month (57%). Cord blood samples were examined in 37 subjects with AD and 51 without AD; of those, 25% showed high levels of total IgE (>1.2 IU/µL), and 51% showed normally-distributed high absorbance IL-5 values (≥0.0715, absolute value was undetected). The increased level of IL-5 was directly proportional to IgE. High absorbance IFN-γ values (≥0.0795, absolute value = 18.681 pg/µL) were observed in 52% of subjects. CONCLUSION: The associations between the risk of allergy in the family, cord-blood total IgE, IL-5, IFN levels, and some perinatal environmental exposure with AD in the first 6 months of life have not been established.
Allergy and Immunology ; Asthma ; Case-Control Studies ; Cohort Studies ; Dermatitis, Atopic ; Environmental Exposure ; Enzyme-Linked Immunosorbent Assay ; Fetal Blood ; Humans ; Hypersensitivity ; Immunoglobulin E ; Immunoglobulins ; Incidence ; Infant, Newborn ; Inflammation ; Interferons ; Interleukin-5 ; Life Style ; Multivariate Analysis ; Rhinitis ; Risk Factors ; Skin

Adult ; Antibodies ; blood ; Antiviral Agents ; therapeutic use ; DNA, Viral ; blood ; Female ; Hepatitis B Surface Antigens ; blood ; Hepatitis B e Antigens ; blood ; Hepatitis B virus ; drug effects ; Hepatitis B, Chronic ; blood ; drug therapy ; virology ; Humans ; Interferons ; immunology ; therapeutic use ; Liver Function Tests ; Male ; Middle Aged ; Young Adult