Infections by coronaviruses such as severe acute respiratory syndrome （SARS） coronavirus （SCoV） and mouse hepatitis virus A59 （MHV-A59） result in very little type I interferon （IFN） production by host cells, w...Infections by coronaviruses such as severe acute respiratory syndrome （SARS） coronavirus （SCoV） and mouse hepatitis virus A59 （MHV-A59） result in very little type I interferon （IFN） production by host cells, which is potentially responsible for the rapid viral growth and severe immunopathology associated with SARS. However, the molecular mechanisms for the low IFN production in cells infected with coronaviruses remain unclear. Here, we provide evidence that Papain-like protease domain 2 （PLP2）, a catalytic domain of the nonstructural protein 3 （nsp3） of MHV-A59, can bind to IRF3, cause its deubiquitination and prevent its nuclear translocation. As a consequence, co-expression of PLP2 strongly inhibits CARDIF-, TBK1- and IRF3-mediated IFNp reporter activities. In addition, we show that wild-type PLP2 but not the mutant PLP2 lacking the deubiquitinase （DUB） activity can reduce IFN induction and promote viral growth in cells infected with VSV. Thus, our study uncovered a viral DUB which coronaviruses may use to escape from the host innate antiviral responses.展开更多
Type I interferons (IFN) are well studied cytokines with anti-viral and immune-modulating functions. Type I IFNsare produced following viral infections, but until recently, the mechanisms of viral recognition leading ...Type I interferons (IFN) are well studied cytokines with anti-viral and immune-modulating functions. Type I IFNsare produced following viral infections, but until recently, the mechanisms of viral recognition leading to IFN productionwere largely unknown. Toll like receptors (TLRs) have emerged as key transducers of type I IFN during viral infectionsby recognizing various viral components. Furthermore, much progress has been made in defining the signaling path-ways downstream of TLRs for type I IFN production. TLR7 and TLR9 have become apparent as universally importantin inducing type I IFN during infection with most viruses, particularly by plasmacytoid dendritic cells. New intracellularviral pattern recognition receptors leading to type I IFN production have been identified. Many bacteria can also inducethe up-regulation of these cytokines. Interestingly, recent studies have found a detrimental effect on host cells if type IIFN is produced during infection with the intracellular gram-positive bacterial pathogen, Listeria monocytogenes. Thisreview will discuss the recent advances made in defining the signaling pathways leading to type I IFN production.展开更多
AIM: To review the prevalence,clinical data and course of interferon-associated type 1 diabetes in chronic hepatitis C virus(HCV) infection.METHODS: Search of all interferon(INF)-related type 1diabetes mellitus(T1DM) ...AIM: To review the prevalence,clinical data and course of interferon-associated type 1 diabetes in chronic hepatitis C virus(HCV) infection.METHODS: Search of all interferon(INF)-related type 1diabetes mellitus(T1DM) cases published in the English literature from 1992 to December 2013 according to the key words: chronic hepatitis C infection,diabetes mellitus type 1,insulin dependent diabetes mellitus,and interferon treatment.We found 107 cases and analyzed their clinical and laboratory data and long-term followup.Due to the predominance of cases described in Japanese literature,we analyzed separately cases of Caucasian and Japanese origin.In addition we describe a representative case with HCV who developed INFrelated T1 DM.RESULTS: Our data show that INF treatment increases the risk of developing T1 DM by 10-18 fold compared with the corresponding general population and the median age of onset was 43 years(range: 24-66 years) in Caucasians and 52 years(range: 45-63 years) in Japanese.Most patients developed T1 DM during INF treatment,after a median time-period of 4.2 and 5.7 mo in Caucasian and Japanese groups,respectively.The clinical course was characterized by a fulminant course with abrupt severe hyperglycemia or ketoacidosis,a high titer of anti-islet autoantibodies and almost all patients(105/107) permanently required insulin therapy with a follow-up of up to 4 years.A substantial number of patients had evidence for other autoimmune disorders mainly thyroid diseases(25% and 31% in Caucasian and Japanese groups,respectively).CONCLUSION: INF-associated T1 DM in HCV has a fulminant course,often associated with other autoimmune diseases,and results almost inevitably in permanent insulin therapy requirement.展开更多
Dendritic cells （DC）, although a minor population in hematopoietic cells, produce type I interferons （IFN） and other cytokines and are essential for innate immunity. They are also potent antigen presenters and reg...Dendritic cells （DC）, although a minor population in hematopoietic cells, produce type I interferons （IFN） and other cytokines and are essential for innate immunity. They are also potent antigen presenters and regulate adaptive immunity. Among DC subtypes plasmacytoid DC （pDC） produce the highest amounts of type I IFN. In addition, pro- and anti-inflammatory cytokines such as IL-12 and IL-10 are induced in DC in response to Toll like receptor （TLR） signaling and upon viral infection. Proteins in the IRF family control many aspects of DC activity. IRF-8 and IRF-4 are essential for DC development. They differentially control the development of four DC subsets. IRF-8^-/- mice are largely devoid of pDC and CD8α^＋ DC, while IRF-4^-/- mice lack CD4^＋ DC. IRF-8^-/-, IRF4^-/-, double knock-out mice have only few CD8α CD4^-DC that lack MHC Ⅱ. IRF proteins also control type Ⅰ IFN induction in DC. IRF-7, activated upon TLR signaling is required for IFN induction not only in pDC, but also in conventional DC （cDC） and non-DC cell types. IRF-3, although contributes to IFN induction in fibroblasts, is dispensable in IFN induction in DC. Our recent evidence reveals that type Ⅰ IFN induction in DC is critically dependent on IRF-8, which acts in the feedback phase of IFN gene induction in DC. Type Ⅰ IFN induction in pDC is mediated by MyD88 dependent signaling pathway, and differs from pathways employed in other cells, which mostly rely on TLR3 and RIG-Ⅰ family proteins. Other pro-inflammatory cytokines are produced in an IRF-5 dependent manner. However, IRF-5 is not required for IFN induction, suggesting the presence of separate mechanisms for induction of type Ⅰ IFN and other pro-inflammatory cytokines. IFN and other cytokines produced by activated DC in turn advance DC maturation and change the phenotype and function of DC. These processes are also likely to be governed by IRF family proteins.展开更多
Type I interferons are critical antiviral cytokines produced following herpes simplex virus type-1 （HSV-1） infection that act to inhibit viral spread. In the present study, we identify HSV-infected and adjacent unin...Type I interferons are critical antiviral cytokines produced following herpes simplex virus type-1 （HSV-1） infection that act to inhibit viral spread. In the present study, we identify HSV-infected and adjacent uninfected corneal epithelial cells as the source of interferon-a. We also report mice deficient in the A1 chain of the type I IFN receptor （CDl18-/） are extremely sensitive to ocular infection with low doses （100 PFU） of HSV-1 as seen by significantly elevated viral titers in the cornea Compared to wild type （WT） controls. The enhanced susceptibil- ity correlated with a loss of CD4＋ and CD8＋ T cell recruitment and aberrant chemokine production in the cornea despite mounting an adaptive immune response in the draining mandibular lymph node of CDll8/ mice. Taken together, these results highlight the importance of IFN production in both the innate immune response as well as eliciting chemokine production required to facilitate adaptive immune cell trafficking.展开更多
Type I interferon(IFN)is considered as a bridge between innate and adaptive immunity.Proper activation or inhibition of type I IFN signaling is essential for host defense against pathogen invasion,tumor cell prolifera...Type I interferon(IFN)is considered as a bridge between innate and adaptive immunity.Proper activation or inhibition of type I IFN signaling is essential for host defense against pathogen invasion,tumor cell proliferation,and overactive immune responses.Due to intricate and diverse chemical structures,natural products and their derivatives have become an invaluable source inspiring innovative drug discovery.In addition,some natural products have been applied in clinical practice for infection,cancer,and autoimmunity over thousands of years and their promising curative effects and safety have been well-accepted.However,whether these natural products are primarily targeting type I IFN signaling and specific molecular targets involved are not fully elucidated.In the current review,we thoroughly summarize recent advances in the pharmacology researches of natural products for their type I IFN activity,including both agonism/activation and antagonism/inhibition,and their potential application as therapies.Furthermore,the source and chemical nature of natural products with type I IFN activity are highlighted and their specific molecular targets in the type I IFN pathway and mode of action are classified.In conclusion,natural products possessing type I IFN activity represent promising therapeutic strategies and have a bright prospect in the treatment of infection,cancer,and autoimmune diseases.展开更多
TypeⅢinterferons(IFNs)represent the most recently discovered group of IFNs.Together with typeⅠIFNs(e.g.IFN-α/β),typeⅢIFNs(IFN-λ)are produced as part of the innate immune response to virus infection,and elicit an...TypeⅢinterferons(IFNs)represent the most recently discovered group of IFNs.Together with typeⅠIFNs(e.g.IFN-α/β),typeⅢIFNs(IFN-λ)are produced as part of the innate immune response to virus infection,and elicit an anti-viral state by inducing expression of interferon stimulated genes(ISGs).It was initially thought that typeⅠIFNs and typeⅢIFNs perform largely redundant functions.However,it has become evident that typeⅢIFNs particularly play a major role in antiviral protection of mucosal epithelial barriers,thereby serving an important role in the first-line defense against virus infection and invasion at contact areas with the outside world,versus the generally more broad,potent and systemic antiviral effects of typeⅠIFNs.Herpesviruseses are large DNA viruses,which enter their host via mucosal surfaces and establish lifelong,latent infections.Despite the importance of mucosal epithelial cells in the pathogenesis of herpesviruses,our current knowledge on the interaction of herpesviruses with typeⅢIFN is limited and largely restricted to studies on the alphaherpesvirus herpes simplex virus(HSV).This review summarizes the current understanding about the role of IFN-λin the immune response against herpesvirus infections.展开更多
As one of the deadliest viruses,Ebola virus(EBOV)causes lethal hemorrhagic fevers in humans and nonhuman primates.The suppression of innate immunity leads to robust systemic virus replication of EBOV,leading to enhanc...As one of the deadliest viruses,Ebola virus(EBOV)causes lethal hemorrhagic fevers in humans and nonhuman primates.The suppression of innate immunity leads to robust systemic virus replication of EBOV,leading to enhanced transmission.However,the mechanism of EBOV-host interaction is not fully understood.Here,we identified multiple dysregulated genes in early stage of EBOV infection through transcriptomic analysis,which are highly clustered to Jak-STAT signaling.EBOV VP35 and VP30 were found to inhibit type I interferon(IFN)signaling.Moreover,exogenous expression of VP35 blocks the phosphorylation of endogenous STAT1,and suppresses nuclear translocation of STAT1.Using serial truncated mutations of VP35,N-terminal 1–220amino acid residues of VP35 were identified to be essential for blocking on type I IFN signaling.Remarkably,VP35 of EBOV suppresses type I IFN signaling more efficiently than those of Bundibugyo virus(BDBV)and Marburg virus(MARV),resulting in stable replication to facilitate the pathogenesis.Altogether,this study enriches understanding on EBOV evasion of innate immune response,and provides insights into the interplay between filoviruses and host.展开更多
African swine fever(ASF)is originally reported in East Africa as an acute hemorrhagic fever.African swine fever virus(ASFV)is a giant and complex DNA virus with icosahedral structure and encodes a variety of virulence...African swine fever(ASF)is originally reported in East Africa as an acute hemorrhagic fever.African swine fever virus(ASFV)is a giant and complex DNA virus with icosahedral structure and encodes a variety of virulence factors to resist host innate immune response.S273R protein(pS273R),as a SUMO-1 specific cysteine protease,can affect viral packaging by cutting polymeric proteins.In this study,we found that pS273R was an important antagonistic viral factor that suppressed cGAS-STING-mediated type I interferon(IFN-I)production.A detailed analysis showed that pS273R inhibited IFN-I production by interacting with interferon regulatory factor 3(IRF3).Subsequently,we showed that pS273R disrupted the association between TBK1 and IRF3,leading to the repressed IRF3 phosphorylation and dimerization.Deletion and point mutation analysis verified that pS273R impaired IFN-I production independent of its cysteine protease activity.These findings will help us further understand ASFV pathogenesis.展开更多
Dengue virus(DENV) and Zika virus(ZIKV) have spread throughout many countries in the developing world and infect millions of people every year, causing severe harm to human health and the economy. Unfortunately, there...Dengue virus(DENV) and Zika virus(ZIKV) have spread throughout many countries in the developing world and infect millions of people every year, causing severe harm to human health and the economy. Unfortunately, there are few effective vaccines and therapies available against these viruses. Therefore, the discovery of new antiviral agents is critical.Herein, a scorpion venom peptide(Smp76) characterized from Scorpio maurus palmatus was successfully expressed and purified in Escherichia coli BL21(DE3). The recombinant Smp76(rSmp76) was found to effectively inhibit DENV and ZIKV infections in a dose-dependent manner in both cultured cell lines and primary mouse macrophages. Interestingly,rSmp76 did not inactivate the viral particles directly but suppressed the established viral infection, similar to the effect of interferon(IFN)-b. Mechanistically, rSmp76 was revealed to upregulate the expression of IFN-b by activating interferon regulatory transcription factor 3(IRF3) phosphorylation, enhancing the type-Ⅰ IFN response and inhibiting viral infection.This mechanism is significantly different from traditional virucidal antimicrobial peptides(AMPs). Overall, the scorpion venom peptide Smp76 is a potential new antiviral agent with a unique mechanism involving type-Ⅰ IFN responses,demonstrating that natural AMPs can enhance immunity by functioning as immunomodulators.展开更多
Objective:To investigate the effects of Sishen pill on the expression of type I interferon(IFN)and type III interferon and their receptors in colonic tissues of mice with acute ulcerative colitis(UC).Methods:Male C57B...Objective:To investigate the effects of Sishen pill on the expression of type I interferon(IFN)and type III interferon and their receptors in colonic tissues of mice with acute ulcerative colitis(UC).Methods:Male C57BL/6Cnc mice were randomly divided into control group,model group,sishenwan group and salazosulfapyridine group.The model was made with 0.2 mL 4%dextran sodium sulfate(DSS)for 5 days,and the control group was given 0.2mL normal saline by gavage.On the second day of modeling,sishen pill group was given 0.2mL 1.5 g·kg^(-1) sishen pill,and SASP group was given 0.2mL 0.25 g·kg^(-1) sulfasalazine,twice a day,for 7 days.During the administration period,the disease activity index(DAI)of mice was calculated every day.After administration,the histopathological changes of colon tissues of mice in each group were observed by hematoxylin eosin(HE)staining,and the histological scores were calculated.The expression of IFN-α,IFN-β,IFN-λ2 and IFN-λ3 mRNAs in colon tissues of mice in each group were detected by qRT-PCR.The expression levels of IFN-α,IFN-β,IFN-λ2 and IFN-λ3 in colon tissues of mice in each group were detected by ELISA.Western blot was used to detect the expression of interferon receptors IFNAR1,IFNAR2 and IFNLR1 in colon tissues of mice in each group.Results:Compared with the control group,the DAI of mice increased significantly(P<0.001)in the model group.The inflammatory cells in colonic tissues infiltrated heavily,lymph nodes enlarged,colonic mucosal structure destroyed,crypt structure lost,inflammation involved a wide range,and the histological score increased significantly(P<0.001).The levels of IFN-α,IFN-βand IFNλ2 mRNA were significantly decreased(P<0.05,P<0.05,P<0.01).The expression levels of IFN-α,IFN-β,IFN-λ2 and IFN-λ3 were significantly decreased(P<0.01,P<0.01,P<0.001,P<0.001).The levels of IFNAR1,IFNAR2 and IFNLR1 were significantly decreased(P<0.01,P<0.05,P<0.01).Compared with the model group,the DAI decreased significantly(P<0.001)in Sishen pill group,the infiltration of inflammatory cells in colon tissue were significantly reduced,the structural regeneration of colon mucosa was significantly recovered,the crypt structure was significantly recovered,the lymph nodes were significantly reduced,the range of inflammation involvement was reduced,and the histological score was significantly reduced(P<0.001).The levels of IFN-α,IFN-βand IFN-λ2 mRNA were significantly increased(P<0.01,P<0.001,P<0.001).The levels of IFN-α,IFN-β,IFN-λ2 and IFN-λ3 were significantly increased(P<0.01,P<0.001,P<0.01,P<0.001).The levels of IFNAR1,IFNAR2 and IFNLR1 were significantly increased(P<0.05,P<0.001,P<0.05).Conclusion:Sishen pill may alleviate the symptoms and signs of mice with acute ulcerative colitis by regulating the expression of type I and type III interferon and their receptors in colon tissues.展开更多
C-di-GMP is one kind of second messengers which plays an important role not only in the regulation of various bacterial physiological activities but also in the activation of innate immune response to induce typeⅠint...C-di-GMP is one kind of second messengers which plays an important role not only in the regulation of various bacterial physiological activities but also in the activation of innate immune response to induce typeⅠinterferon in mammalian cells.In this assay,by using one-pot phosphoramidite method,three novel kinds of analogs of c-di-GMP including its phosphorthiates modified by ganciclovir(7 a,7 b,7 c)have been designed and synthesized.The immune-stimulatory results of these c-di-GMP analogs in RAW-Lucia ISG cells indicated that they couldn’t induce the release of typeⅠinterferon,which demonstrated that the intact structure of ribose moieties is very vital for their bioactivity upon the activation of STING signaling pathway.展开更多
A number of cytokines are secreted during HIV infection that enhances both innate and adaptive immune responses. Interferon-α/β/γ, IL-12, IL-15 and IL-18 have been found to contribute to the development, maturation...A number of cytokines are secreted during HIV infection that enhances both innate and adaptive immune responses. Interferon-α/β/γ, IL-12, IL-15 and IL-18 have been found to contribute to the development, maturation, differentiation and function of NK and other immune cells. The levels of IFN-α/β/γ, IL-12, IL-15 and IL-18 were compared in the plasma of 90 HIV-1 infected and 90 HIV-2 infected subjects by ELISA or Cytometric Beads Array assays. The HIV-infected subjects were stratified according to CD4<sup>+</sup> T cell counts into three groups: >500, 200 - 500 and <200 cells/ul, with 30 subjects in each group. Cytokine levels were also determined in the plasma of 50 HIV uninfected blood bank donors. Among the cytokines tested, IFN-α was found to be significantly increased in HIV-2 infected compared to HIV-1 infected subjects at high CD4<sup>+</sup> T cell counts (p = 0.001). The levels of IFN-β were seen to differ between the two infections in patients from the category of medium CD4<sup>+</sup> T cell counts: this was significantly increased in HIV-2 infected patients (p < 0.001) as well as compared to uninfected controls (p = 0.001). The levels of IFN-γ were similar at all the CD4<sup>+</sup> T cell categories except for an increase in HIV-2 infected patients at low CD4<sup>+</sup> T cell counts (p = 0.02). The levels of these cytokines were similar in all HIV-1 subjects. Also, the level of IL-12p70 was similar between the two infections but significantly higher in HIV-2 at low compared to medium CD4<sup>+</sup> T cells categories (p = 0.047). Similar to IFN-γ and IL-12p70, the levels of both IL-18 and IL-15 were found to be significantly higher in HIV-2 infected patients compared to HIV-1 at low CD4<sup>+</sup> T cell counts (p < 0.05). These data show that there is variability in the levels of innate cytokines at different stages of HIV infection but the finding of increased IFN-α in HIV-2 infected asymptomatic subjects is consistent with the high innate NK responses previously noted at this stage of infection.展开更多
Crimean-Congo hemorrhagic fever virus(CCHFV)is a biosafety level-4(BSL-4)pathogen that causes Crimean-Congo hemorrhagic fever(CCHF)characterized by hemorrhagic manifestation,multiple organ failure and high mortality r...Crimean-Congo hemorrhagic fever virus(CCHFV)is a biosafety level-4(BSL-4)pathogen that causes Crimean-Congo hemorrhagic fever(CCHF)characterized by hemorrhagic manifestation,multiple organ failure and high mortality rate,posing great threat to public health.Despite the recently increasing research efforts on CCHFV,host cell responses associated with CCHFV infection remain to be further characterized.Here,to better understand the cellular response to CCHFV infection,we performed a transcriptomic analysis in human kidney HEK293 cells by high-throughput RNA sequencing(RNA-seq)technology.In total,496 differentially expressed genes(DEGs),including 361 up-regulated and 135 down-regulated genes,were identified in CCHFV-infected cells.These regulated genes were mainly involved in host processes including defense response to virus,response to stress,regulation of viral process,immune response,metabolism,stimulus,apoptosis and protein catabolic process.Therein,a significant up-regulation of type III interferon(IFN)signaling pathway as well as endoplasmic reticulum(ER)stress response was especially remarkable.Subsequently,representative DEGs from these processes were well validated by RT-qPCR,confirming the RNA-seq results and the typical regulation of IFN responses and ER stress by CCHFV.Furthermore,we demonstrate that not only type I but also type III IFNs(even at low dosages)have substantial anti-CCHFV activities.Collectively,the data may provide new and comprehensive insights into the virus-host interactions and particularly highlights the potential role of type III IFNs in restricting CCHFV,which may help inform further mechanistic delineation of the viral infection and development of anti-CCHFV strategies.展开更多
Interferon regulatory factor 7 plays a crucial role in the innate immune response.However,whether interferon regulatory factor 7-mediated signaling contributes to Parkinson's disease remains unknown.Here we report...Interferon regulatory factor 7 plays a crucial role in the innate immune response.However,whether interferon regulatory factor 7-mediated signaling contributes to Parkinson's disease remains unknown.Here we report that interferon regulatory factor 7 is markedly up-regulated in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of Parkinson's disease and co-localizes with microglial cells.Both the selective cyclic guanosine monophosphate adenosine monophosphate synthase inhibitor RU.521 and the stimulator of interferon genes inhibitor H151 effectively suppressed interferon regulatory factor 7 activation in BV2 microglia exposed to 1-methyl-4-phenylpyridinium and inhibited transformation of mouse BV2 microglia into the neurotoxic M1 phenotype.In addition,si RNA-mediated knockdown of interferon regulatory factor 7 expression in BV2 microglia reduced the expression of inducible nitric oxide synthase,tumor necrosis factorα,CD16,CD32,and CD86 and increased the expression of the anti-inflammatory markers ARG1 and YM1.Taken together,our findings indicate that the cyclic guanosine monophosphate adenosine monophosphate synthase-stimulator of interferon genes-interferon regulatory factor 7 pathway plays a crucial role in the pathogenesis of Parkinson's disease.展开更多
AIMS To clarify whether the lower interferon gamma (IFNγ) production by lymphocytes in patients with liver diseases is due to defects of lymphocytes themselves or of other cofactors such as interleukin-2(IL-2). METHO...AIMS To clarify whether the lower interferon gamma (IFNγ) production by lymphocytes in patients with liver diseases is due to defects of lymphocytes themselves or of other cofactors such as interleukin-2(IL-2). METHODS Peripheral blood mononuclear cells (PBMCs) from patients with various liver diseases were cultured with or without PHA and IL-2. The cells were harvested and counted and the su- pernatants were tested for IFNγ by a sensitive and quantitative ABC-ELISA. RESULTS IFNγ was not round in serum samples from patients as well as normal individuals. However,in supernatants of non-in- duced and induced PBMCs,IFN7 was detected by ABC-ELISA. In non-induced PBMCs (group 1),the content of IFNγ in super- natants from control,CAH,CPH and HCC was 8.72 μg/L, 5.03 μg/L,6.02 μg/L and 4.91 μg/L respectively. The pro- duction of IFNγ in liver disease was significantly decreased,com- pared to control. In group 2 in which PBMCs were stimulated with PHA,the content of IFNγ was 22.71,17.12,14.54 and 17.63 μg/L respectively. In group 3 in which PBMCs were in- duced by IL-2,the amount of IFN7 in supernatant from control (60.67 μg/L) was much larger than those from CAH (21.70 μg/ L),CPH (24.00 μg/L) and HCC (19.15 μg/L) (P<0.01). Comparing the amount of IFNγ in group 3 (IL-2-induced) with that in group 1 (non-induced),we found that IFNγ production was en- hanced by nearly 4 folds in liver diseases and by over 7 folds in control,Whereas the number of PBMCs,whether from liver dis- eases or from control,was increased by only approximately 3 folds. CONCLUSIONS The decreased production of IFNγ in liver dis- eases including HCC is mainly due to endogenous defects of lym- phocytes though the defects of stimulating cofactors such as IL-2 may also be involved.展开更多
BACKGROUND： The supernatant of interferon-gamma （IFNγ） co-cultured with neonatal rat cortical glia can promote the cells in embryonic basal forebrain/septal nuclei to differentiate into cholinergic neurons, but th...BACKGROUND： The supernatant of interferon-gamma （IFNγ） co-cultured with neonatal rat cortical glia can promote the cells in embryonic basal forebrain/septal nuclei to differentiate into cholinergic neurons, but the mechanism is still unclear. OBJECTIVE： To analyze the pathways for IFNγ to promote the differentiation of primarily cultured cholinergic neurons in rat embryonic basal forebrain/septal nuclei through culture in different conditioned medium. DESIGN： A controlled experiment taking cells as the observational target. SETTINGS： Department of Biochemistry and Molecular Biology, Youjiang Medical College for Nationalities; Department of Cell Biology, Beijing University Health Science Center. MATERIALS： Sixty-four pregnant Wistar rats for 16 days （250-350 g） and 84 Wistar rats （either male or female, 5-7 g） of 0-1 day after birth were provided by the experimental animal department of Beijing University Health Science Center. Rat IFNγ were provided by Gibco Company; Glial fibrillary acidic protein by Huamei Company. METHODS： The experiments were carried out in the Department of Cell Biology, Beijing University Health Science Center and Daheng Image Company of Chinese Academy of Science from July 1995 to December 2002. ① Interventions： The nerve cells in the basal forebrain/septal nuclei of the pregnant Wistar rats for 16 days were primarily cultured, and then divided into four groups： Blank control group （not any supernatant and medium was added）; Control group （added by mixed glial cell or astrocyte conditioned medium）; IFNγ group （added by mixed glial cell or astrocyte conditioned medium＋IFNγ）. Antibody group （added by mixed glial cell or astrocyte conditioned medium＋IFNγ＋Ab-IFNγ）. Mixed glial cell or astrocyte conditioned medium was prepared using cerebral cortex of Wistar rats of 0-1 day after birth. ② Evaluation： The immunohistochemical method was used to perform the choline acetyltransferase （ChAT） staining of cholinergic neurons. The ChAT positive cells were counted. MAIN OUTCOME MEASURES： Comparison of ChAT positive cells in rat basal forebrain and septal nuclei in different conditioned medium. RESULTS： ① ChAT positive cells in mixed glial cell conditioned medium： The ChAT positive cells in the IFNγ group and antibody group were significantly more than those in the control group （P 〈 0.01）. ② ChAT positive cells in astrocyte conditioned medium： The ChAT positive cells in the IFNγ group were significantly more than those in the control group, but there was no significant difference between the antibody group and control group （P 〉 0.05）. CONCLUSION： IFNγ cannot directly promote the differentiation of cholinergic neurons, but plays a role through activating glial cells （except astrocytes） to produce IFNγ like molecules.展开更多
Japanese encephalitis virus(JEV) is a mosquito-borne virus and the major cause of viral encephalitis in Asia. NS1', a52-amino acid C-terminal extension of NS1, is generated with a-1 programmed ribosomal frameshift...Japanese encephalitis virus(JEV) is a mosquito-borne virus and the major cause of viral encephalitis in Asia. NS1', a52-amino acid C-terminal extension of NS1, is generated with a-1 programmed ribosomal frameshift and is only present in members of the Japanese encephalitis serogroup of flaviviruses. Previous studies demonstrated that NS1' plays a vital role in virulence, but the mechanism is unclear. In this study, an NS1' defected(rG66A) virus was generated. We found that rG66A virus was less virulent than its parent virus(pSA14) in wild-type mice. However, similar mortality caused by the two viruses was observed in an IFNAR knockout mouse model. Moreover, we found that rG66A virus induced a greater type Ⅰ interferon(IFN) response than that by pSA14, and JEV NS1' significantly inhibited the production of IFN-b and IFN-stimulated genes. Taken together, our results reveal that NS1' plays a vital role in blocking type I IFN production to help JEV evade antiviral immunity and benefit viral replication.展开更多
During infections,nucleic acids of pathogens are also engaged in recognition via several exogenous and cytosolic pattern recognition receptors,such as the toll-like receptors,retinoic acid inducible gene-I-like recept...During infections,nucleic acids of pathogens are also engaged in recognition via several exogenous and cytosolic pattern recognition receptors,such as the toll-like receptors,retinoic acid inducible gene-I-like receptors,and nucleotide-binding and oligomerization domain-like receptors.The binding of the pathogen-derived nucleic acids to their corresponding sensors initiates certain downstream signaling cascades culminating in the release of type-I interferons(IFNs),especially IFN-αand other cytokines to induce proinflammatory responses towards invading pathogens leading to their clearance from the host.Although these sensors are hardwired to recognize pathogen associated molecular patterns,like viral and bacterial nucleic acids,under unusual physiological conditions,such as excessive cellular stress and increased apoptosis,endogenous self-nucleic acids like DNA,RNA,and mitochondrial DNA are also released.The presence of these self-nucleic acids in extranuclear compartments or extracellular spaces or their association with certain proteins sometimes leads to the failure of discriminating mechanisms of nucleic acid sensors leading to proinflammatory responses as seen in autoimmune disorders,like systemic lupus erythematosus,psoriasis and to some extent in type 1 diabetes(T1D).This review discusses the involvement of various nucleic acid sensors in autoimmunity and discusses how aberrant recognition of self-nucleic acids by their sensors activates the innate immune responses during the pathogenesis of T1D.展开更多
基金These authors contributed equally to this work. We thank Drs S Vaidya and E Chow （University of California Los Angeles, USA） for their help in setting up critical experimental systems. We greatly thank Dr K Holmes （University of Colorado Health Sciences Center, USA） for sharing with us 17C1-1 cell line and helping to optimize the protocol to produce high titered MHV-A59 virus stock. We also thank Drs R Baric and L Su （University of North Carolina, USA） for the gift of MHV-A59 and guidance of virus infection. We thank Dr K Lim （National Neuroscience Institute, Singapore） for the gift of Ubi plasmids. We thank Dr M Wathelet （University of Cincinnati College of Medicine, USA） for sharing the nsp3 construct. Also we thank Dr G Gao （Institute of Biophysics, CAS） for providing us with VSV. This research was partly supported by grants from the National Natural Science Foundation of China （30728006） to Genhong Cheng and the National Basic Research Program of MOST （2004BA519A61, 2006CB504300, 2007DFC30190） to Hong Tang.
文摘Infections by coronaviruses such as severe acute respiratory syndrome （SARS） coronavirus （SCoV） and mouse hepatitis virus A59 （MHV-A59） result in very little type I interferon （IFN） production by host cells, which is potentially responsible for the rapid viral growth and severe immunopathology associated with SARS. However, the molecular mechanisms for the low IFN production in cells infected with coronaviruses remain unclear. Here, we provide evidence that Papain-like protease domain 2 （PLP2）, a catalytic domain of the nonstructural protein 3 （nsp3） of MHV-A59, can bind to IRF3, cause its deubiquitination and prevent its nuclear translocation. As a consequence, co-expression of PLP2 strongly inhibits CARDIF-, TBK1- and IRF3-mediated IFNp reporter activities. In addition, we show that wild-type PLP2 but not the mutant PLP2 lacking the deubiquitinase （DUB） activity can reduce IFN induction and promote viral growth in cells infected with VSV. Thus, our study uncovered a viral DUB which coronaviruses may use to escape from the host innate antiviral responses.
基金A. K. Perry is supported by the Howard Hughes Medi-cal Institute predoctoral fellowship (Grant No. 59003787).Part of this work was also supported by National Insti-tutes of Health research grants RO1 CA87924, RO1AI056154, and R37 AI47868 to G. Cheng and from the MajorResearch Plan (30170461, 30430640) +1 种基金Natural ScienceFoundation of China, and the National Basic ResearchProgram of MOST (2002CB513001, 2001CB-510002)H. Tang. H. Tang is also a fellow of Outstanding YoungInvestigators of National Naturual Science Foundation ofChina (30025010).
文摘Type I interferons (IFN) are well studied cytokines with anti-viral and immune-modulating functions. Type I IFNsare produced following viral infections, but until recently, the mechanisms of viral recognition leading to IFN productionwere largely unknown. Toll like receptors (TLRs) have emerged as key transducers of type I IFN during viral infectionsby recognizing various viral components. Furthermore, much progress has been made in defining the signaling path-ways downstream of TLRs for type I IFN production. TLR7 and TLR9 have become apparent as universally importantin inducing type I IFN during infection with most viruses, particularly by plasmacytoid dendritic cells. New intracellularviral pattern recognition receptors leading to type I IFN production have been identified. Many bacteria can also inducethe up-regulation of these cytokines. Interestingly, recent studies have found a detrimental effect on host cells if type IIFN is produced during infection with the intracellular gram-positive bacterial pathogen, Listeria monocytogenes. Thisreview will discuss the recent advances made in defining the signaling pathways leading to type I IFN production.
文摘AIM: To review the prevalence,clinical data and course of interferon-associated type 1 diabetes in chronic hepatitis C virus(HCV) infection.METHODS: Search of all interferon(INF)-related type 1diabetes mellitus(T1DM) cases published in the English literature from 1992 to December 2013 according to the key words: chronic hepatitis C infection,diabetes mellitus type 1,insulin dependent diabetes mellitus,and interferon treatment.We found 107 cases and analyzed their clinical and laboratory data and long-term followup.Due to the predominance of cases described in Japanese literature,we analyzed separately cases of Caucasian and Japanese origin.In addition we describe a representative case with HCV who developed INFrelated T1 DM.RESULTS: Our data show that INF treatment increases the risk of developing T1 DM by 10-18 fold compared with the corresponding general population and the median age of onset was 43 years(range: 24-66 years) in Caucasians and 52 years(range: 45-63 years) in Japanese.Most patients developed T1 DM during INF treatment,after a median time-period of 4.2 and 5.7 mo in Caucasian and Japanese groups,respectively.The clinical course was characterized by a fulminant course with abrupt severe hyperglycemia or ketoacidosis,a high titer of anti-islet autoantibodies and almost all patients(105/107) permanently required insulin therapy with a follow-up of up to 4 years.A substantial number of patients had evidence for other autoimmune disorders mainly thyroid diseases(25% and 31% in Caucasian and Japanese groups,respectively).CONCLUSION: INF-associated T1 DM in HCV has a fulminant course,often associated with other autoimmune diseases,and results almost inevitably in permanent insulin therapy requirement.
文摘Dendritic cells （DC）, although a minor population in hematopoietic cells, produce type I interferons （IFN） and other cytokines and are essential for innate immunity. They are also potent antigen presenters and regulate adaptive immunity. Among DC subtypes plasmacytoid DC （pDC） produce the highest amounts of type I IFN. In addition, pro- and anti-inflammatory cytokines such as IL-12 and IL-10 are induced in DC in response to Toll like receptor （TLR） signaling and upon viral infection. Proteins in the IRF family control many aspects of DC activity. IRF-8 and IRF-4 are essential for DC development. They differentially control the development of four DC subsets. IRF-8^-/- mice are largely devoid of pDC and CD8α^＋ DC, while IRF-4^-/- mice lack CD4^＋ DC. IRF-8^-/-, IRF4^-/-, double knock-out mice have only few CD8α CD4^-DC that lack MHC Ⅱ. IRF proteins also control type Ⅰ IFN induction in DC. IRF-7, activated upon TLR signaling is required for IFN induction not only in pDC, but also in conventional DC （cDC） and non-DC cell types. IRF-3, although contributes to IFN induction in fibroblasts, is dispensable in IFN induction in DC. Our recent evidence reveals that type Ⅰ IFN induction in DC is critically dependent on IRF-8, which acts in the feedback phase of IFN gene induction in DC. Type Ⅰ IFN induction in pDC is mediated by MyD88 dependent signaling pathway, and differs from pathways employed in other cells, which mostly rely on TLR3 and RIG-Ⅰ family proteins. Other pro-inflammatory cytokines are produced in an IRF-5 dependent manner. However, IRF-5 is not required for IFN induction, suggesting the presence of separate mechanisms for induction of type Ⅰ IFN and other pro-inflammatory cytokines. IFN and other cytokines produced by activated DC in turn advance DC maturation and change the phenotype and function of DC. These processes are also likely to be governed by IRF family proteins.
基金supported by USPHS grant (No. AI053108) to DanielJ.J. CarrP20 (No. RR017703)+1 种基金an unrestricted grant from Research to Prevent Blindnesssupported by NIAID training grant(No. AI007633)
文摘Type I interferons are critical antiviral cytokines produced following herpes simplex virus type-1 （HSV-1） infection that act to inhibit viral spread. In the present study, we identify HSV-infected and adjacent uninfected corneal epithelial cells as the source of interferon-a. We also report mice deficient in the A1 chain of the type I IFN receptor （CDl18-/） are extremely sensitive to ocular infection with low doses （100 PFU） of HSV-1 as seen by significantly elevated viral titers in the cornea Compared to wild type （WT） controls. The enhanced susceptibil- ity correlated with a loss of CD4＋ and CD8＋ T cell recruitment and aberrant chemokine production in the cornea despite mounting an adaptive immune response in the draining mandibular lymph node of CDll8/ mice. Taken together, these results highlight the importance of IFN production in both the innate immune response as well as eliciting chemokine production required to facilitate adaptive immune cell trafficking.
基金This work was supported by Beijing Nova Program of Science&Technology(Nos.Z201100006820025 and Z211100002121167)the Young Elite Scientists Sponsorship Program from CACM(No.CACM-2020-QNRC2-04)the National Natural Science Foundation of China(No.82004029).
文摘Type I interferon(IFN)is considered as a bridge between innate and adaptive immunity.Proper activation or inhibition of type I IFN signaling is essential for host defense against pathogen invasion,tumor cell proliferation,and overactive immune responses.Due to intricate and diverse chemical structures,natural products and their derivatives have become an invaluable source inspiring innovative drug discovery.In addition,some natural products have been applied in clinical practice for infection,cancer,and autoimmunity over thousands of years and their promising curative effects and safety have been well-accepted.However,whether these natural products are primarily targeting type I IFN signaling and specific molecular targets involved are not fully elucidated.In the current review,we thoroughly summarize recent advances in the pharmacology researches of natural products for their type I IFN activity,including both agonism/activation and antagonism/inhibition,and their potential application as therapies.Furthermore,the source and chemical nature of natural products with type I IFN activity are highlighted and their specific molecular targets in the type I IFN pathway and mode of action are classified.In conclusion,natural products possessing type I IFN activity represent promising therapeutic strategies and have a bright prospect in the treatment of infection,cancer,and autoimmune diseases.
基金Research of YY and HWF is supported by grants from the Special Research Fund of Ghent University(CSC-cofunding grant and Concerted Research Action GOA013-17).
文摘TypeⅢinterferons(IFNs)represent the most recently discovered group of IFNs.Together with typeⅠIFNs(e.g.IFN-α/β),typeⅢIFNs(IFN-λ)are produced as part of the innate immune response to virus infection,and elicit an anti-viral state by inducing expression of interferon stimulated genes(ISGs).It was initially thought that typeⅠIFNs and typeⅢIFNs perform largely redundant functions.However,it has become evident that typeⅢIFNs particularly play a major role in antiviral protection of mucosal epithelial barriers,thereby serving an important role in the first-line defense against virus infection and invasion at contact areas with the outside world,versus the generally more broad,potent and systemic antiviral effects of typeⅠIFNs.Herpesviruseses are large DNA viruses,which enter their host via mucosal surfaces and establish lifelong,latent infections.Despite the importance of mucosal epithelial cells in the pathogenesis of herpesviruses,our current knowledge on the interaction of herpesviruses with typeⅢIFN is limited and largely restricted to studies on the alphaherpesvirus herpes simplex virus(HSV).This review summarizes the current understanding about the role of IFN-λin the immune response against herpesvirus infections.
基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0490000)the National Natural Science Foundation of China(82202521).
文摘As one of the deadliest viruses,Ebola virus(EBOV)causes lethal hemorrhagic fevers in humans and nonhuman primates.The suppression of innate immunity leads to robust systemic virus replication of EBOV,leading to enhanced transmission.However,the mechanism of EBOV-host interaction is not fully understood.Here,we identified multiple dysregulated genes in early stage of EBOV infection through transcriptomic analysis,which are highly clustered to Jak-STAT signaling.EBOV VP35 and VP30 were found to inhibit type I interferon(IFN)signaling.Moreover,exogenous expression of VP35 blocks the phosphorylation of endogenous STAT1,and suppresses nuclear translocation of STAT1.Using serial truncated mutations of VP35,N-terminal 1–220amino acid residues of VP35 were identified to be essential for blocking on type I IFN signaling.Remarkably,VP35 of EBOV suppresses type I IFN signaling more efficiently than those of Bundibugyo virus(BDBV)and Marburg virus(MARV),resulting in stable replication to facilitate the pathogenesis.Altogether,this study enriches understanding on EBOV evasion of innate immune response,and provides insights into the interplay between filoviruses and host.
基金the National Natural Science Foundation of China(Grant No.32172869),China.
文摘African swine fever(ASF)is originally reported in East Africa as an acute hemorrhagic fever.African swine fever virus(ASFV)is a giant and complex DNA virus with icosahedral structure and encodes a variety of virulence factors to resist host innate immune response.S273R protein(pS273R),as a SUMO-1 specific cysteine protease,can affect viral packaging by cutting polymeric proteins.In this study,we found that pS273R was an important antagonistic viral factor that suppressed cGAS-STING-mediated type I interferon(IFN-I)production.A detailed analysis showed that pS273R inhibited IFN-I production by interacting with interferon regulatory factor 3(IRF3).Subsequently,we showed that pS273R disrupted the association between TBK1 and IRF3,leading to the repressed IRF3 phosphorylation and dimerization.Deletion and point mutation analysis verified that pS273R impaired IFN-I production independent of its cysteine protease activity.These findings will help us further understand ASFV pathogenesis.
基金supported by grants from National Science Fund of China (Nos. 31572289, 31872239 and 81630091)International S&T Cooperation Program of China (No. S2016G3110)+3 种基金Hubei Science Fund (Nos. 2015CFA042 and 2016CFA018)China-Kazakhstan Cooperation Program (No. CK-07-09)Fundamental Research Funds for the Central Universities in China (Nos. 2042017kf0242 and 2042017kf0199)financial support from Higher Education Commission (HEC) of Pakistan
文摘Dengue virus(DENV) and Zika virus(ZIKV) have spread throughout many countries in the developing world and infect millions of people every year, causing severe harm to human health and the economy. Unfortunately, there are few effective vaccines and therapies available against these viruses. Therefore, the discovery of new antiviral agents is critical.Herein, a scorpion venom peptide(Smp76) characterized from Scorpio maurus palmatus was successfully expressed and purified in Escherichia coli BL21(DE3). The recombinant Smp76(rSmp76) was found to effectively inhibit DENV and ZIKV infections in a dose-dependent manner in both cultured cell lines and primary mouse macrophages. Interestingly,rSmp76 did not inactivate the viral particles directly but suppressed the established viral infection, similar to the effect of interferon(IFN)-b. Mechanistically, rSmp76 was revealed to upregulate the expression of IFN-b by activating interferon regulatory transcription factor 3(IRF3) phosphorylation, enhancing the type-Ⅰ IFN response and inhibiting viral infection.This mechanism is significantly different from traditional virucidal antimicrobial peptides(AMPs). Overall, the scorpion venom peptide Smp76 is a potential new antiviral agent with a unique mechanism involving type-Ⅰ IFN responses,demonstrating that natural AMPs can enhance immunity by functioning as immunomodulators.
基金National Natural Science Foundation of China(No.82160835)。
文摘Objective:To investigate the effects of Sishen pill on the expression of type I interferon(IFN)and type III interferon and their receptors in colonic tissues of mice with acute ulcerative colitis(UC).Methods:Male C57BL/6Cnc mice were randomly divided into control group,model group,sishenwan group and salazosulfapyridine group.The model was made with 0.2 mL 4%dextran sodium sulfate(DSS)for 5 days,and the control group was given 0.2mL normal saline by gavage.On the second day of modeling,sishen pill group was given 0.2mL 1.5 g·kg^(-1) sishen pill,and SASP group was given 0.2mL 0.25 g·kg^(-1) sulfasalazine,twice a day,for 7 days.During the administration period,the disease activity index(DAI)of mice was calculated every day.After administration,the histopathological changes of colon tissues of mice in each group were observed by hematoxylin eosin(HE)staining,and the histological scores were calculated.The expression of IFN-α,IFN-β,IFN-λ2 and IFN-λ3 mRNAs in colon tissues of mice in each group were detected by qRT-PCR.The expression levels of IFN-α,IFN-β,IFN-λ2 and IFN-λ3 in colon tissues of mice in each group were detected by ELISA.Western blot was used to detect the expression of interferon receptors IFNAR1,IFNAR2 and IFNLR1 in colon tissues of mice in each group.Results:Compared with the control group,the DAI of mice increased significantly(P<0.001)in the model group.The inflammatory cells in colonic tissues infiltrated heavily,lymph nodes enlarged,colonic mucosal structure destroyed,crypt structure lost,inflammation involved a wide range,and the histological score increased significantly(P<0.001).The levels of IFN-α,IFN-βand IFNλ2 mRNA were significantly decreased(P<0.05,P<0.05,P<0.01).The expression levels of IFN-α,IFN-β,IFN-λ2 and IFN-λ3 were significantly decreased(P<0.01,P<0.01,P<0.001,P<0.001).The levels of IFNAR1,IFNAR2 and IFNLR1 were significantly decreased(P<0.01,P<0.05,P<0.01).Compared with the model group,the DAI decreased significantly(P<0.001)in Sishen pill group,the infiltration of inflammatory cells in colon tissue were significantly reduced,the structural regeneration of colon mucosa was significantly recovered,the crypt structure was significantly recovered,the lymph nodes were significantly reduced,the range of inflammation involvement was reduced,and the histological score was significantly reduced(P<0.001).The levels of IFN-α,IFN-βand IFN-λ2 mRNA were significantly increased(P<0.01,P<0.001,P<0.001).The levels of IFN-α,IFN-β,IFN-λ2 and IFN-λ3 were significantly increased(P<0.01,P<0.001,P<0.01,P<0.001).The levels of IFNAR1,IFNAR2 and IFNLR1 were significantly increased(P<0.05,P<0.001,P<0.05).Conclusion:Sishen pill may alleviate the symptoms and signs of mice with acute ulcerative colitis by regulating the expression of type I and type III interferon and their receptors in colon tissues.
基金National Natural Science Foundation of China(Grant No.U1604285,21572013)
文摘C-di-GMP is one kind of second messengers which plays an important role not only in the regulation of various bacterial physiological activities but also in the activation of innate immune response to induce typeⅠinterferon in mammalian cells.In this assay,by using one-pot phosphoramidite method,three novel kinds of analogs of c-di-GMP including its phosphorthiates modified by ganciclovir(7 a,7 b,7 c)have been designed and synthesized.The immune-stimulatory results of these c-di-GMP analogs in RAW-Lucia ISG cells indicated that they couldn’t induce the release of typeⅠinterferon,which demonstrated that the intact structure of ribose moieties is very vital for their bioactivity upon the activation of STING signaling pathway.
文摘A number of cytokines are secreted during HIV infection that enhances both innate and adaptive immune responses. Interferon-α/β/γ, IL-12, IL-15 and IL-18 have been found to contribute to the development, maturation, differentiation and function of NK and other immune cells. The levels of IFN-α/β/γ, IL-12, IL-15 and IL-18 were compared in the plasma of 90 HIV-1 infected and 90 HIV-2 infected subjects by ELISA or Cytometric Beads Array assays. The HIV-infected subjects were stratified according to CD4<sup>+</sup> T cell counts into three groups: >500, 200 - 500 and <200 cells/ul, with 30 subjects in each group. Cytokine levels were also determined in the plasma of 50 HIV uninfected blood bank donors. Among the cytokines tested, IFN-α was found to be significantly increased in HIV-2 infected compared to HIV-1 infected subjects at high CD4<sup>+</sup> T cell counts (p = 0.001). The levels of IFN-β were seen to differ between the two infections in patients from the category of medium CD4<sup>+</sup> T cell counts: this was significantly increased in HIV-2 infected patients (p < 0.001) as well as compared to uninfected controls (p = 0.001). The levels of IFN-γ were similar at all the CD4<sup>+</sup> T cell categories except for an increase in HIV-2 infected patients at low CD4<sup>+</sup> T cell counts (p = 0.02). The levels of these cytokines were similar in all HIV-1 subjects. Also, the level of IL-12p70 was similar between the two infections but significantly higher in HIV-2 at low compared to medium CD4<sup>+</sup> T cells categories (p = 0.047). Similar to IFN-γ and IL-12p70, the levels of both IL-18 and IL-15 were found to be significantly higher in HIV-2 infected patients compared to HIV-1 at low CD4<sup>+</sup> T cell counts (p < 0.05). These data show that there is variability in the levels of innate cytokines at different stages of HIV infection but the finding of increased IFN-α in HIV-2 infected asymptomatic subjects is consistent with the high innate NK responses previously noted at this stage of infection.
基金supported by the National Key Research and Development Program of China(2018YFA0507202)the National Natural Science Foundation of China(32170171,31870162,and 82161138003)the Youth Innovation Promotion Association of Chinese Academy of Sciences.
文摘Crimean-Congo hemorrhagic fever virus(CCHFV)is a biosafety level-4(BSL-4)pathogen that causes Crimean-Congo hemorrhagic fever(CCHF)characterized by hemorrhagic manifestation,multiple organ failure and high mortality rate,posing great threat to public health.Despite the recently increasing research efforts on CCHFV,host cell responses associated with CCHFV infection remain to be further characterized.Here,to better understand the cellular response to CCHFV infection,we performed a transcriptomic analysis in human kidney HEK293 cells by high-throughput RNA sequencing(RNA-seq)technology.In total,496 differentially expressed genes(DEGs),including 361 up-regulated and 135 down-regulated genes,were identified in CCHFV-infected cells.These regulated genes were mainly involved in host processes including defense response to virus,response to stress,regulation of viral process,immune response,metabolism,stimulus,apoptosis and protein catabolic process.Therein,a significant up-regulation of type III interferon(IFN)signaling pathway as well as endoplasmic reticulum(ER)stress response was especially remarkable.Subsequently,representative DEGs from these processes were well validated by RT-qPCR,confirming the RNA-seq results and the typical regulation of IFN responses and ER stress by CCHFV.Furthermore,we demonstrate that not only type I but also type III IFNs(even at low dosages)have substantial anti-CCHFV activities.Collectively,the data may provide new and comprehensive insights into the virus-host interactions and particularly highlights the potential role of type III IFNs in restricting CCHFV,which may help inform further mechanistic delineation of the viral infection and development of anti-CCHFV strategies.
基金supported by the National Natural Science Foundation of China,Nos.82171429,81771384a grant from Wuxi Municipal Health Commission,No.1286010241190480(all to YS)。
文摘Interferon regulatory factor 7 plays a crucial role in the innate immune response.However,whether interferon regulatory factor 7-mediated signaling contributes to Parkinson's disease remains unknown.Here we report that interferon regulatory factor 7 is markedly up-regulated in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of Parkinson's disease and co-localizes with microglial cells.Both the selective cyclic guanosine monophosphate adenosine monophosphate synthase inhibitor RU.521 and the stimulator of interferon genes inhibitor H151 effectively suppressed interferon regulatory factor 7 activation in BV2 microglia exposed to 1-methyl-4-phenylpyridinium and inhibited transformation of mouse BV2 microglia into the neurotoxic M1 phenotype.In addition,si RNA-mediated knockdown of interferon regulatory factor 7 expression in BV2 microglia reduced the expression of inducible nitric oxide synthase,tumor necrosis factorα,CD16,CD32,and CD86 and increased the expression of the anti-inflammatory markers ARG1 and YM1.Taken together,our findings indicate that the cyclic guanosine monophosphate adenosine monophosphate synthase-stimulator of interferon genes-interferon regulatory factor 7 pathway plays a crucial role in the pathogenesis of Parkinson's disease.
基金Supported by National Science Fundation of China.No.89138970378.
文摘AIMS To clarify whether the lower interferon gamma (IFNγ) production by lymphocytes in patients with liver diseases is due to defects of lymphocytes themselves or of other cofactors such as interleukin-2(IL-2). METHODS Peripheral blood mononuclear cells (PBMCs) from patients with various liver diseases were cultured with or without PHA and IL-2. The cells were harvested and counted and the su- pernatants were tested for IFNγ by a sensitive and quantitative ABC-ELISA. RESULTS IFNγ was not round in serum samples from patients as well as normal individuals. However,in supernatants of non-in- duced and induced PBMCs,IFN7 was detected by ABC-ELISA. In non-induced PBMCs (group 1),the content of IFNγ in super- natants from control,CAH,CPH and HCC was 8.72 μg/L, 5.03 μg/L,6.02 μg/L and 4.91 μg/L respectively. The pro- duction of IFNγ in liver disease was significantly decreased,com- pared to control. In group 2 in which PBMCs were stimulated with PHA,the content of IFNγ was 22.71,17.12,14.54 and 17.63 μg/L respectively. In group 3 in which PBMCs were in- duced by IL-2,the amount of IFN7 in supernatant from control (60.67 μg/L) was much larger than those from CAH (21.70 μg/ L),CPH (24.00 μg/L) and HCC (19.15 μg/L) (P<0.01). Comparing the amount of IFNγ in group 3 (IL-2-induced) with that in group 1 (non-induced),we found that IFNγ production was en- hanced by nearly 4 folds in liver diseases and by over 7 folds in control,Whereas the number of PBMCs,whether from liver dis- eases or from control,was increased by only approximately 3 folds. CONCLUSIONS The decreased production of IFNγ in liver dis- eases including HCC is mainly due to endogenous defects of lym- phocytes though the defects of stimulating cofactors such as IL-2 may also be involved.
基金the National Natural Science Foundation of China, No. 39570249
文摘BACKGROUND： The supernatant of interferon-gamma （IFNγ） co-cultured with neonatal rat cortical glia can promote the cells in embryonic basal forebrain/septal nuclei to differentiate into cholinergic neurons, but the mechanism is still unclear. OBJECTIVE： To analyze the pathways for IFNγ to promote the differentiation of primarily cultured cholinergic neurons in rat embryonic basal forebrain/septal nuclei through culture in different conditioned medium. DESIGN： A controlled experiment taking cells as the observational target. SETTINGS： Department of Biochemistry and Molecular Biology, Youjiang Medical College for Nationalities; Department of Cell Biology, Beijing University Health Science Center. MATERIALS： Sixty-four pregnant Wistar rats for 16 days （250-350 g） and 84 Wistar rats （either male or female, 5-7 g） of 0-1 day after birth were provided by the experimental animal department of Beijing University Health Science Center. Rat IFNγ were provided by Gibco Company; Glial fibrillary acidic protein by Huamei Company. METHODS： The experiments were carried out in the Department of Cell Biology, Beijing University Health Science Center and Daheng Image Company of Chinese Academy of Science from July 1995 to December 2002. ① Interventions： The nerve cells in the basal forebrain/septal nuclei of the pregnant Wistar rats for 16 days were primarily cultured, and then divided into four groups： Blank control group （not any supernatant and medium was added）; Control group （added by mixed glial cell or astrocyte conditioned medium）; IFNγ group （added by mixed glial cell or astrocyte conditioned medium＋IFNγ）. Antibody group （added by mixed glial cell or astrocyte conditioned medium＋IFNγ＋Ab-IFNγ）. Mixed glial cell or astrocyte conditioned medium was prepared using cerebral cortex of Wistar rats of 0-1 day after birth. ② Evaluation： The immunohistochemical method was used to perform the choline acetyltransferase （ChAT） staining of cholinergic neurons. The ChAT positive cells were counted. MAIN OUTCOME MEASURES： Comparison of ChAT positive cells in rat basal forebrain and septal nuclei in different conditioned medium. RESULTS： ① ChAT positive cells in mixed glial cell conditioned medium： The ChAT positive cells in the IFNγ group and antibody group were significantly more than those in the control group （P 〈 0.01）. ② ChAT positive cells in astrocyte conditioned medium： The ChAT positive cells in the IFNγ group were significantly more than those in the control group, but there was no significant difference between the antibody group and control group （P 〉 0.05）. CONCLUSION： IFNγ cannot directly promote the differentiation of cholinergic neurons, but plays a role through activating glial cells （except astrocytes） to produce IFNγ like molecules.
基金supported by the National Key Research and Development Program of China (2016YFD0500407)National Natural Science Foundation of China (31502065 and 31572517)Fundamental Research Funds for the Central Universities (2013PY051, 2662016Q003, and 2662015PY083)
文摘Japanese encephalitis virus(JEV) is a mosquito-borne virus and the major cause of viral encephalitis in Asia. NS1', a52-amino acid C-terminal extension of NS1, is generated with a-1 programmed ribosomal frameshift and is only present in members of the Japanese encephalitis serogroup of flaviviruses. Previous studies demonstrated that NS1' plays a vital role in virulence, but the mechanism is unclear. In this study, an NS1' defected(rG66A) virus was generated. We found that rG66A virus was less virulent than its parent virus(pSA14) in wild-type mice. However, similar mortality caused by the two viruses was observed in an IFNAR knockout mouse model. Moreover, we found that rG66A virus induced a greater type Ⅰ interferon(IFN) response than that by pSA14, and JEV NS1' significantly inhibited the production of IFN-b and IFN-stimulated genes. Taken together, our results reveal that NS1' plays a vital role in blocking type I IFN production to help JEV evade antiviral immunity and benefit viral replication.
文摘During infections,nucleic acids of pathogens are also engaged in recognition via several exogenous and cytosolic pattern recognition receptors,such as the toll-like receptors,retinoic acid inducible gene-I-like receptors,and nucleotide-binding and oligomerization domain-like receptors.The binding of the pathogen-derived nucleic acids to their corresponding sensors initiates certain downstream signaling cascades culminating in the release of type-I interferons(IFNs),especially IFN-αand other cytokines to induce proinflammatory responses towards invading pathogens leading to their clearance from the host.Although these sensors are hardwired to recognize pathogen associated molecular patterns,like viral and bacterial nucleic acids,under unusual physiological conditions,such as excessive cellular stress and increased apoptosis,endogenous self-nucleic acids like DNA,RNA,and mitochondrial DNA are also released.The presence of these self-nucleic acids in extranuclear compartments or extracellular spaces or their association with certain proteins sometimes leads to the failure of discriminating mechanisms of nucleic acid sensors leading to proinflammatory responses as seen in autoimmune disorders,like systemic lupus erythematosus,psoriasis and to some extent in type 1 diabetes(T1D).This review discusses the involvement of various nucleic acid sensors in autoimmunity and discusses how aberrant recognition of self-nucleic acids by their sensors activates the innate immune responses during the pathogenesis of T1D.
