The cGAS-STING-interferon regulatory factor 7 pathway regulates neuroinflammation in Parkinson's disease

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.

Brain endothelial cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STING)signaling pathway in aging and neurodegeneration

The cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STING)signaling pathway has emerged as a key mediator of neuroinflammation.While current studies primarily attribute its effects to neurons and glial cells,emerging research suggests that cGAS-STING signaling may play a critical role in cerebral vasculature,particularly in brain endothelial cells.Therefore,studying the role 7of inflammation caused by the cGAS-STING pathway in brain endothelial cells could provide a more comprehensive understanding of neuroinflammatory disease and new avenues for therapeutic interventions.Here,we review the multifaceted role of global cGAS-STING signaling in various neurological and neuroinflammatory diseases and the potential contribution of cGAS-STING in brain endothelial cells.

Expression level of interferon-stimulated genes PKR,OAS1,MX1,and ISG15 in peripheral blood mononuclear cells of COVID-19 patients:A retrospective study

Objective:To explore expression level of interferon-stimulated genes PKR,OAS1,MX1,and ISG15 in peripheral blood mononuclear cells of COVID-19 patients.Methods:In this study,changes in the expression of four interferon-stimulated genes(ISGs),including PKR,OAS1,MX1,and ISG15,in peripheral blood mononuclear cells of 45 COVID-19 patients with different severities were evaluated by real-time PCR method.Results:OAS1,MX1,PKR,and ISG15 were differently expressed in COVID-19 patients with different severity.The results showed that the expression of OAS1,MX1,PKR,and ISG15 genes was significantly(P=0.001)lower in severe patients.Conclusions:Weak and defective IFN response and subsequent disruption of ISGs may be associated with COVID-19 severity.

Relationship between Phenotypic Changes of Dendritic Cell Subsets and the Onset of Plateau Phase during Intermittent Interferon Therapy in Patients with CHB

Objective This study aimed to evaluate whether the onset of the plateau phase of slow hepatitis B surface antigen decline in patients with chronic hepatitis B treated with intermittent interferon therapy is related to the frequency of dendritic cell subsets and expression of the costimulatory molecules CD40,CD80,CD83,and CD86.Method This was a cross-sectional study in which patients were divided into a natural history group(namely NH group),a long-term oral nucleoside analogs treatment group(namely NA group),and a plateau-arriving group(namely P group).The percentage of plasmacytoid dendritic cell and myeloid dendritic cell subsets in peripheral blood lymphocytes and monocytes and the mean fluorescence intensity of their surface costimulatory molecules were detected using a flow cytometer.Results In total,143 patients were enrolled(NH group,n=49;NA group,n=47;P group,n=47).The results demonstrated that CD141/CD1c double negative myeloid dendritic cell(DNmDC)/lymphocytes and monocytes(%)in P group(0.041[0.024,0.069])was significantly lower than that in NH group(0.270[0.135,0.407])and NA group(0.273[0.150,0.443]),and CD86 mean fluorescence intensity of DNmDCs in P group(1832.0[1484.0,2793.0])was significantly lower than that in NH group(4316.0[2958.0,5169.0])and NA group(3299.0[2534.0,4371.0]),Adjusted P all<0.001.Conclusion Reduced DNmDCs and impaired maturation may be associated with the onset of the plateau phase during intermittent interferon therapy in patients with chronic hepatitis B.

Gut microbial metabolite targets HDAC3-FOXK1-interferon axis in fibroblast-like synoviocytes to ameliorate rheumatoid arthritis

Rheumatoid arthritis(RA)is an autoimmune disease.Early studies hold an opinion that gut microbiota is environmentally acquired and associated with RA susceptibility.However,accumulating evidence demonstrates that genetics also shape the gut microbiota.It is known that some strains of inbred laboratory mice are highly susceptible to collagen-induced arthritis(CIA),while the others are resistant to CIA.Here,we show that transplantation of fecal microbiota of CIA-resistant C57BL/6J mice to CIA-susceptible DBA/1J mice confer CIA resistance in DBA/1J mice.C57BL/6J mice and healthy human individuals have enriched B.fragilis than DBA/1J mice and RA patients.Transplantation of B.fragilis prevents CIA in DBA/1J mice.We identify that B.fragilis mainly produces propionate and C57BL/6J mice and healthy human individuals have higher level of propionate.Fibroblast-like synoviocytes(FLSs)in RA are activated to undergo tumor-like transformation.Propionate disrupts HDAC3-FOXK1 interaction to increase acetylation of FOXK1,resulting in reduced FOXK1 stability,blocked interferon signaling and deactivation of RA-FLSs.We treat CIA mice with propionate and show that propionate attenuates CIA.Moreover,a combination of propionate with anti-TNF etanercept synergistically relieves CIA.These results suggest that B.fragilis or propionate could be an alternative or complementary approach to the current therapies.

Role of cyclic guanosine monophosphate-adenosine monophosphate synthase-stimulator of interferon genes pathway in diabetes and its complications

Diabetes mellitus(DM)is one of the major causes of mortality worldwide,with inflammation being an important factor in its onset and development.This review summarizes the specific mechanisms of the cyclic guanosine monophosphate-adenosine monophosphate synthase(cGAS)-stimulator of interferon genes(STING)pathway in mediating inflammatory responses.Furthermore,it compre-hensively presents related research progress and the subsequent involvement of this pathway in the pathogenesis of early-stage DM,diabetic gastroenteropathy,diabetic cardiomyopathy,non-alcoholic fatty liver disease,and other complic-ations.Additionally,the role of cGAS-STING in autonomic dysfunction and intes-tinal dysregulation,which can lead to digestive complications,has been discuss-ed.Altogether,this study provides a comprehensive analysis of the research advances regarding the cGAS-STING pathway-targeted therapeutic agents and the prospects for their application in the precision treatment of DM.

Evaluation of Interferon-Gamma Release Assay Testing and Tuberculin Skin Test for Early Diagnosis of Tuberculosis in Children and Adolescents

Background: This study aimed to evaluate the diagnostic value of interferon-γ release assay (IGRA), a sensitive microbiological diagnostic method, in children and adolescents with suspected tuberculosis in a country with a high burden of tuberculosis. Method: This study included 581 children and adolescents aged 4 - 19 years who were suspected of having tuberculosis, were latently infected with Mycobacterium tuberculosis, and had received at least one dose of BCG vaccine between April 17, 2019, and February 24, 2021. The study evaluated the TST results of 106 patients who had a positive Quantiferon test and were suspected of having tuberculosis. Results: The study included 581 patients aged between 4 and 19 years. Of these, 106 patients tested positive for the Quantiferon test, while 19 were indeterminate and 456 were negative. The Quantiferon test positivity rate was 18.24%. Among the 106 QFT-Plus-positive cases, 23 patients also tested positive for TST. The difference in distribution was found to be statistically significant. Conclusion: The QFT-Plus test is considered an alternative to TST and other microbiological diagnostic methods for early tuberculosis diagnosis, particularly in children and adolescents.

Impact of hepatitis C virus heterogeneity on interferon sensitivity:An overview

Hepatitis C virus(HCV)is a major cause of liver disease worldwide.HCV is able to evade host defense mechanisms,including both innate and acquired immune responses,to establish persistent infection,which results in a broad spectrum of pathogenicity,such as lipid and glucose metabolism disorders and hepatocellular carcinoma development.The HCV genome is characterized by a high degree of genetic diversity,which can be associated with viral sensitivity or resistance(reflected by different virological responses)to interferon(IFN)-based therapy.In this regard,it is of importance to note that polymorphisms in certain HCV genomic regions have shown a close correlation with treatment outcome.In particular,among the HCV proteins,the core and nonstructural proteins(NS)5A have been extensively studied for their correlation with responses to IFN-based treatment.This review aims to cover updated information on the impact of major HCV genetic factors,including HCV genotype,mutations in amino acids 70 and91 of the core protein and sequence heterogeneity in the IFN sensitivity-determining region and IFN/ribavirin resistance-determining region of NS5A,on virological responses to IFN-based therapy.

Interferon regulatory factor 2 binding protein 2:a new player of the innate immune response for stroke recovery

Ischemic brain injury triggers an inflammatory response. tissue but can also exacerbate brain injury. Microglia are This response is necessary to clear damaged brain the innate immune cells of the brain that execute this critical function. In healthy brain, microglia perform a housekeeping function, pruning unused syn- apses between neurons. However, microglia become activated to an inflammatory phenotype upon brain injury. Interferon regulatory factors modulate microglial activation and their production of inflammatory cytokines. This review briefly discusses recent findings pertaining to these regulatory mechanisms in the context of stroke recovery.

Effects of hepatitis E virus infection on interferon production via ISG15

AIM To assess the effects of hepatitis E virus(HEV) on the production of type Ⅰ interferons(IFNs) and determine the underlying mechanisms.METHODS We measured the production of interferon(IFN)-alpha and-beta(-α/β) in genotype 3 HEV-infected C3 A cells at different time points(0, 8, 12, 24, 48, 72 and 120 h) by enzyme-linked immunosorbent assay(ELISA). The expression levels of IFN-stimulated gene(ISG)15 in HEVinfected C3A cells at different time points were tested by western blotting. The plasmid-expressing open reading frame 3(ORF3) or control plasmids(green fluorescent protein-expressing) were transfected into C3A cells, and the levels of IFN-α/β and ISG15 were evaluated, respectively. Furthermore, the plasmid-expressing ISG15 or small interfering RNA-inhibiting ISG15 was transfected into infected C3A cells. Then, the production of IFN-α/β was also measured by ELISA.RESULTS We showed that genotype 3 HEV could enhance the production of IFN-α/β and induce elevation of ISG15 in C3A cells. HEV ORF3 protein could enhance the production of IFN-α/β and the expression of ISG15. Additionally, ISG15 silencing enhanced the production of IFN-α/β. Overexpression of ISG15 resulted in the reduction of IFN-α/β.CONCLUSION HEV may promote production of IFN-α/β and expression of ISG15 via ORF3 in the early stages, and increased ISG15 subsequently inhibited the production of IFN-α/β.

Role of interferons in diabetic retinopathy

Diabetic retinopathy(DR)is one of the major causes of visual impairment and irreversible blindness in developed regions.Aside from abnormal angiogenesis,inflammation is the most specific and might be the initiating factor of DR.As a key participant in inflammation,interferon-gamma(IFN-γ)can be detected in different parts of the eye and is responsible for the breakdown of the blood-retina barrier and activation of inflammatory cells and other cytokines,which accelerate neovascularization and neuroglial degeneration.In addition,IFN-γis involved in other vascular complications of diabetes mellitus and angiogenesis-dependent diseases,such as diabetic nephropathy,cerebral microbleeds,and age-related macular degeneration.Traditional treatments,such as anti-vascular endothelial growth factor agents,vitrectomy,and laser photocoagulation therapy,are more effective for angiogenesis and not tolerable for every patient.Many ongoing clinical trials are exploring effective drugs that target inflammation.For instance,IFN-αacts against viruses and angiogenesis and is commonly used to treat malignant tumors.Moreover,IFN-αhas been shown to contribute to alleviating the progression of DR and other ocular diseases.In this review,we emphasize the roles that IFNs play in the pathogenesis of DR and discuss potential clinical applications of IFNs in DR,such as diagnosis,prognosis,and therapeutic treatment.

Control of hepatitis B virus replication by interferons and Toll-like receptor signaling pathways

Hepatitis B virus (HBV) infection is one of the major causes of liver diseases, affecting more than 350 million people worldwide. The interferon (IFN)-mediated innate immune responses could restrict HBV replication at the different steps of viral life cycle. Indeed, IFN-&#x003b1; has been successfully used for treatment of patients with chronic hepatitis B. However, the role of the innate immune response in HBV replication and the mechanism of the anti-HBV effect of IFN-&#x003b1; are not completely explored. In this review, we summarized the currently available knowledge about the IFN-mediated anti-HBV effect in the HBV life cycle and the possible effectors downstream the IFN signaling pathway. The antiviral effect of Toll-like receptors (TLRs) in HBV replication is briefly discussed. The strategies exploited by HBV to evade the IFN- and TLR-mediated antiviral actions are summarized.

Psychiatric side effects of pegylated interferon alfa-2b as compared to conventional interferon alfa-2b in patients with chronic hepatitis C

AIM: To assess systematically the spectrum and extent of depressive symptoms comparing patient groups receiving peginterferon or conventional interferon.METHODS: Ninety-eight patients with chronic hepatitis C and interferon-based therapy (+ribavirin) were consecutively enrolled in a longitudinal study. Patients were treated with conventional interferon alfa-2b (48/98patients; 5 MIU interferon alfa-2b thrice weekly) or peginterferon alfa-2b (50/98 patients; 80-150 μgpeginterferon alfa-2b) in combination with weight-adapted ribavirin (800-1 200 mg/d). Repeated psychometric testing was performed before, three times during and once after antiviral therapy: Depression was evaluated by the Hospital Anxiety and Depression Scale (HADS), anger/hostility by the Symptom Checklist-90 Items Revised (SCL-90-R).RESULTS: Therapy with pegylated interferon alfa-2bproduces comparable scores for depression (ANOVA:P = 0.875) as compared to conventional interferon.Maximums of depression scores were even higher and cases of clinically relevant depression were frequent during therapy with peginterferon. Scores for anger/hostility were comparable for both therapy subgroups.CONCLUSION: Our findings suggest that the extent and frequency of depressive symptoms in total are not reduced by peginterferon. Monitoring and management of neuropsychiatric toxicity especially depression have to be considered as much as in antiviral therapy with unmodified interferon.

Interferon-associated retinopathy risk in patients with diabetes and hypertensive hepatitis C

AIM: To investigate the association of hypertension and diabetes mellitus (DM) with interferon-associated retinopathy (IAR) risk in chronic hepatitis C (CHC).

Hepatitis B surface antigen clearance in inactive hepatitis B surface antigen carriers treated with peginterferon alfa-2a

AIM: To examine the association between interferon(IFN) therapy and loss of hepatitis B surface antigen(HBs Ag) in inactive HBs Ag carriers. METHODS: This was a retrospective cohort study in inactive HBs Ag carriers, who were treatment-naive, with a serum HBs Ag level < 100 IU/m L and an undetectable hepatitis B virus(HBV) DNA level(< 100 IU/m L). All the 20 treated patients received subcutaneous PEG-IFN alfa-2a 180 μg/wk for 72 wk and were then followed for 24 wk. There were 40 untreated controls matched with 96 wk of observation. Serum HBs Ag, HBV DNA, and alanine aminotransferases were monitored every 3 mo in the treatment group and every 3-6 mo in the control group. RESULTS: Thirteen(65.0%) of 20 treated patients achieved HBs Ag loss, 12 of whom achieved HBs Ag seroconversion. Mean HBs Ag level in treated patients decreased to 6.69 ± 13.04 IU/m L after 24 wk of treatment from a baseline level of 26.22 ± 33.00 IU/m L. Serum HBV DNA level remained undetectable(< 100 IU/m L) in all treated patients during the study. HBs Ag level of the control group decreased from 25.72 ± 25.58 IU/m L at baseline to 17.11 ± 21.62 IU/m L at week 96(P = 0.108). In the control group, no patient experienced HBs Ag loss/seroconversion, and two(5.0%) developed HBV reactivation.CONCLUSION: IFN treatment results in HBs Ag loss and seroconversion in a considerable proportion of inactive HBs Ag carriers with low HBs Ag concentrations.

DNA-dependent activator of interferon-regulatory factors inhibits hepatitis B virus replication

AIM： To investigate whether DNA-dependent activator of interferon-regulatory factors （DAI） inhibits hepatitis B virus （HBV） replication and what the mechanism is. METHODS： After the human hepatoma cell line Huh7 was cotransfected with DAI and HBV expressing plas- mid, viral protein （HBV surface antigen and HBV e an- tigen） secretion was detected by enzyme-linked immu- nosorbent assay, and HBV RNA was analyzed by real- time polymerase chain reaction and Northern blotting, and viral DNA replicative intermediates were examined by Southern blotting. Interferon regulatory factor 3 （IRF3） phosphorylation and nuclear translocation were analyzed via Western blotting and immunofluorescence staining respectively. Nuclear factor-KB （NF-KB） activity induced by DAI was detected by immunofluorescence staining of P65 and dual luciferase reporter assay. Tran- swell co-culture experiment was performed in order to investigate whether the antiviral effects of DAI were dependent on the secreted cytokines. RESULTS： Viral protein secretion was significantly re- duced by 57% （P 〈 0.05）, and the level of total HBV RNA was reduced by 67% （P 〈 0.05）. The viral core particle-associated DNA was also dramatically down- regulated in DAI-expressing Huh7 cells. Analysis of involved signaling pathways revealed that activation of NF-KB signaling was essential for DAI to elicit antivi- ral response in Huh7 cells. When the NF-KB signaling pathway was blocked by a NF-KB signaling suppressor （I~：B^-SR）, the anti-HBV activity of DAI was remarkably abrogated. The inhibitory effect of DAI was indepen- dent of IRF3 signaling and secreted cytokines. CONCLUSION： This study demonstrates that DAI can inhibit HBV replication and the inhibitory effect is asso- ciated with activation of NF-KB but independent of IRF3 and secreted cytokines.

Factors associated with the response to interferon-based antiviral therapies for chronic hepatitis C

Hepatitis C virus(HCV) infection is a major health concern worldwide. Interferon-α(IFN-α) therapy has been the main antiviral treatment for more than 20 years. Because of its established antitumor effects, IFNbased treatments for chronic HCV infection still have a clinical impact, particularly for patients with high risk conditions of developing hepatocellular carcinoma, such as older age and advanced liver fibrosis. As a result of exhaustive research, several viral factors, including NS5 A amino acid mutations such as the IFN sensitivitydetermining region and the IFN/ribavirin resistancedetermining region, and mutations of amino acids in the core protein region(core 70 and 91) were shown to be associated with the response to IFN-α treatment. In addition, among the host factors related to the response to IFN-α treatment, polymorphisms of the interleukin-28 B gene were identified to be the most important factor. In this article, we review the factors associated with the efficacy of IFN-α treatment for chronic HCV infection. In addition, our recent findings regarding the possible involvement of anti-IFN-α neutralizing antibodies in a non-response to pegylated-IFN-α treatment are also described.

Characterization of the antiviral effects of interferon-α against a SARS-like coronoavirus infection in vitro

Interferon （IFN）-αs bind to and activate their cognate cell surface receptor to invoke an antiviral response in target cells. Well-described receptor-mediated signaling events result in transcriptional regulation of IFN sensitive genes, effectors of this antiviral response. Results from a pilot study to evaluate the clinical efficacy of IFN-α treatment of SARS patients provided evidence for IFN-inducible resolution of disease. In this report we examined the contribution of IFN-inducible phosphorylation-activation of specific signaling effectors to protection from infection by a SARS-related murine coronavirus, MHV-1. As anticipated, the earliest receptor-activation event, Jakl phosphorylation, is critical for IFN-inducible protection from MHV-1 infection. Additionally, we provide evidence for the contribution of two kinases, the MAP kinase p38MAPK, and protein kinase C （PKC） 5 to antiviral protection from MHV-1 infection. Notably, our data suggest that MHV^I infection, as for the Urbani SARS coronoavirus, inhibits an IFN response, inferred from the lack of activation ofpkr and 2 ＇5 ＇-oas, genes associated with mediating the antiviral activities of IFN-as. To identify potential target genes that are activated downstream of the IFN-inducible signaling effectors we identified, and that mediate protection from coronavirus infection, we examined the gene expression profiles in the peripheral blood mononuclear cells of SARS patients who received IFN treatment. A subset of differentially regulated genes were distinguished with functional properties associated with antimicrobial activities.

Mutations around interferon sensitivity-determining region:A pilot resistance report of hepatitis C virus 1b in a Hong Kong population

AIM： To explore mutations around the interferon sensitivity-determining region （ISDR） which are associated with the resistance of hepatitis C virus lb （HCV-lb） to interferon-α treatment. METHODS： Thirty-seven HCV-lb samples were obtained from Hong Kong patients who had completed the combined interferon-α/ribavirin treatment for more than one year with available response data. Nineteen of them were sustained virological responders, while 18 were non-responders. The amino acid sequences of the extended ISDR （eISDR） covering 64 amino acids upstream and 67 amino acids downstream from the previously reported ISDR were analyzed. RESULTS： One amino acid variation （I2268V, P = 0.023） was significantly correlated with treatment outcome in this pilot study with a limited number of patients, while two amino acid variations （R2260H, P = 0.05 and $2278T, P = 0.05） were weakly associated with treat- ment outcome. The extent of amino acid variations within the ISDR or eISDR was not correlated with treat- ment outcome as previously reported. CONCLUSION： Three amino acid mutations near but outside of ISDR may associate with interferon treatment resistance of HCV-lb patients in Hong Kong.

Interferon-alfa in the treatment of chronic hepatitis B

BACKGROUND: Interferon-alfa has been used in the treat-ment of chronic hepatitis B for more than 20 years and hasits own advantages including a definite course of therapy,no production of drug-resistant variants, and sustained effi-cacy. This review was to understand the role of interferon-alfa therapy in chronic hepatitis B.DATA RESOURCES: An English-language literature searchusing Medscape and MEDLINE was performed and a totalof 48 articles on the treatment of chronic hepatitis with in-terferon-alfa or pegylated interferon-alfa were selected.RESULTS: Interferon-alfa therapy was associated with ahigher HBV DNA inhibition rate and HBeAg loss rate com-pared with controls, and it may have long-term beneficialeffects in terms of HBV clearance, reduction of hepatocel-lular carcinoma, and prolongation of survival. Pegylatedinterferon-alfa was more effective than conventional inter-feron-alfa in the treatment of chronic hepatitis B as well aschronic hepatitis C, and was also associated with greater ef-ficacy than conventional interferon in difficult-to-treat dis-ease.CONCLUSIONS: Interferon-alfa is still regarded as one ofthe first-line drugs for the treatment of chronic hepatitis B.Pegylated interferon is a more promising therapy than con-ventional interferon-alfa, especially in patients with refrac-tory chronic hepatitis B.