目的探讨白细胞介素10(interleukin-10,IL-10)、interferon-γ(IFN-γ)在腺样体肥大(adenoidal hypertrophy,AH)导致分泌性中耳炎(otitis media with effusion,OME)发生发展中的作用。方法以2015年5月~2016年12月期间完成腺样体切除术...目的探讨白细胞介素10(interleukin-10,IL-10)、interferon-γ(IFN-γ)在腺样体肥大(adenoidal hypertrophy,AH)导致分泌性中耳炎(otitis media with effusion,OME)发生发展中的作用。方法以2015年5月~2016年12月期间完成腺样体切除术的72例腺样体肥大患儿为研究对象,其中单纯腺样体肥大42例(单纯AH组),伴OME的腺样体肥大30例(AH伴OME组),以20例同期住院行甲状舌管囊肿切除或者耳前瘘管切除手术且腺样体正常大小患儿做对照组,采用ELISA方法检测所有研究对象腺样体组织和外周血中IL-10、IFN-γ的表达水平,比较各组结果。结果AH伴OME组、单纯AH组腺样体组织中的IL-10浓度分别为125.95±21.74、51.62±18.79 pg/l,明显高于正常对照组(27.48±10.52 pg/L)(P<0.05),AH伴OME组高于单纯AH组,差异也有统计学意义(P<0.05);AH伴OME组、单纯AH组腺样体组织的IFN-γ浓度分别为622.35±72.14和610.27±45.18 pg/l,两组间差异无统计学意义(P>0.05),但高于正常对照组(341.18±32.11 pg/l),差异有统计学意义(P<0.05);AH伴OME组IFN-γ/IL-10比值明显低于AH组和正常对照组(P<0.01);三组间外周血中IL-10、IFN-γ以及IFN-γ/IL-10值差异无统计学意义(P>0.05)。结论AH伴OME组患儿腺样体组织中IFN-γ/IL-10比值下降,致Th1/Th2失衡,推测以IFN-γ/IL-10比值下降为代表的TH2优势可能是腺样体肥大导致分泌性中耳炎的发病机制之一。展开更多
Hantaan virus(HTNV)is a rodent-borne virus that causes hemorrhagic fever with renal syndrome(HFRS),resulting in a high mortality rate of 15%.Interferons(IFNs)play a critical role in the anti-hantaviral immune response...Hantaan virus(HTNV)is a rodent-borne virus that causes hemorrhagic fever with renal syndrome(HFRS),resulting in a high mortality rate of 15%.Interferons(IFNs)play a critical role in the anti-hantaviral immune response,and IFN pretreatment efficiently restricts HTNV infection by triggering the expression of a series of IFNstimulated genes(ISGs)through the Janus kinase-signal transducer and activator of transcription 1(JAK-STAT)pathway.However,the tremendous amount of IFNs produced during late infection could not restrain HTNV replication,and the mechanism remains unclear.Here,we demonstrated that receptor-interacting protein kinase 3(RIPK3),a crucial molecule that mediates necroptosis,was activated by HTNV and contributed to hantavirus evasion of IFN responses by inhibiting STAT1 phosphorylation.RNA-seq analysis revealed the upregulation of multiple cell death-related genes after HTNV infection,with RIPK3 identified as a key modulator of viral replication.RIPK3 ablation significantly enhanced ISGs expression and restrained HTNV replication,without affecting the expression of pattern recognition receptors(PRRs)or the production of type I IFNs.Conversely,exogenously expressed RIPK3 compromised the host's antiviral response and facilitated HTNV replication.RIPK3^(-/-)mice also maintained a robust ability to clear HTNV with enhanced innate immune responses.Mechanistically,we found that RIPK3 could bind STAT1 and inhibit STAT1 phosphorylation dependent on the protein kinase domain(PKD)of RIPK3 but not its kinase activity.Overall,these observations demonstrated a noncanonical function of RIPK3 during viral infection and have elucidated a novel host innate immunity evasion strategy utilized by HTNV.展开更多
为检测SLE患者外周血γ干扰素诱导蛋白10(interferon gamma-induced protein 10,IP-10)的表达情况并探索其临床意义及调控机制,采集上海交通大学医学院附属仁济医院SLE患者和健康体检者外周血,ELISA检测血清中IP-10和IFN-α水平。结果显...为检测SLE患者外周血γ干扰素诱导蛋白10(interferon gamma-induced protein 10,IP-10)的表达情况并探索其临床意义及调控机制,采集上海交通大学医学院附属仁济医院SLE患者和健康体检者外周血,ELISA检测血清中IP-10和IFN-α水平。结果显示,IP-10在SLE患者血清中的水平明显高于对照者(P<0.05);同时根据SLEDAI评分将患者分为无活动组(0~5分)、低活动度组(5~10分)和高活动度组(10分以上)后,发现SLE患者血清中IP-10水平与SLEDAI评分呈明显正相关(r=0.5703,P<0.05)。FACS检测外周血IP-10+细胞类型,发现高活动度组中IP-10+B细胞、NK细胞和单核细胞百分比明显高于低活动度组和正常对照组。用IFN-α刺激SLE患者和健康人PBMC,发现两组培养上清中IP-10水平明显高于未刺激组,但两组间差异无统计学意义(P>0.05);其中IP-10+B细胞百分比也显著升高,并且患者组升高更明显(均P<0.05)。上述结果提示SLE患者中B细胞在IFN-α作用下直接活化产生抗体的同时,也可通过分泌IP-10参与病理性炎症反应,这揭示了B细胞参与SLE发生发展的新机制。展开更多
Cytokines are involved in directing the activation of natural killer （NK） cells. NK cells are involved in the recognition of cells that have been altered; thus they do not recognize specific insults to the host, but...Cytokines are involved in directing the activation of natural killer （NK） cells. NK cells are involved in the recognition of cells that have been altered; thus they do not recognize specific insults to the host, but when activated, are capable of destroying infected cells directly, as well as promoting the recruitment and response of the other components of the immune system by the release of cytokines and chemokines. It is these properties that have made NK cells a critical part of innate immunity and adaptive immunity, and they play a principal role linking innate and adaptive immunity by the recruitment of an adaptive immune response to an innate immune reaction.展开更多
Vertebrate interferon(IFN)expression is fine-tuned in order to avoid excessive tissue injury under normal conditions and during virus infection.FinTRIM(fish novel TRIM,FTR)proteins are reported to regulate the fish IF...Vertebrate interferon(IFN)expression is fine-tuned in order to avoid excessive tissue injury under normal conditions and during virus infection.FinTRIM(fish novel TRIM,FTR)proteins are reported to regulate the fish IFN response.Here,we identify a novel finTRIM gene from yellow catfish(Pelteobagrus fulvidraco),which is sequentially named PfFTR100 according to the nomenclature rule in zebrafish.Genome-wide analyses reveal that FTR100 is unique to Otomorpha fish,with a single copy in spite of additional genome duplication in some fish species.Considering that few of the 99 finTRIM genes identified in zebrafish are conserved in main fish branches and most,such as FTR100,are unique to distinct branches due to lineage-specific expansion of finTRIM genes,we develop a nomenclature for newly cloned finTRIM genes from different fish species.PfFTR100 mRNA is not induced by virus infection,with a relatively high expression level comparable to that of cellular IFN and some IFN-stimulated genes(ISGs)in virally-infected tissues.However,ectopically-expressed PfFTR100 protein is attenuated in virally-infected cells through the proteasomal-dependent pathway.Overexpression of PfFTR100 promotes SVCV replication by downregulating the constitutive and inducible IFN response via a mechanism by which PfFTR100 targets IRF3 and IRF7 to attenuate their mRNA levels rather than their protein levels.Our results indicate that yellow catfish FTR100 is essential for homeostatic regulation of fish tonic IFN response.展开更多
In mammals,mitofusin 2(MFN2)is involved in mitochondrial fusion,and suppresses the virus-induced RIG-I-like receptor(RLR)signaling pathway.However,little is known about the function of MFN2 in non-mammalian species.In...In mammals,mitofusin 2(MFN2)is involved in mitochondrial fusion,and suppresses the virus-induced RIG-I-like receptor(RLR)signaling pathway.However,little is known about the function of MFN2 in non-mammalian species.In the present study,we cloned an MFN2 ortholog(LcMFN2)in large yellow croaker(Larimichthys crocea).Phylogenetic analysis showed that MFN2 emerged after the divergence of amphioxus and vertebrates.The protein sequences of MFN2 were well conserved from fsh to mammals.LcMFN2 was expressed in all the tissues/organs examined at diferent levels,and its expression was upregulated in response to poly(I:C)stimulation.Overexpression of LcMFN2 inhibited MAVS-induced type I interferon(IFN)promoter activation and antiviral gene expression.In contrast,knockdown of endogenous LcMFN2 enhanced poly(I:C)induced production of type I IFNs.Additionally,LcMFN2 enhanced K48-linked polyubiquitination of MAVS,promoting its degradation.Also,overexpression of LcMFN2 impaired the cellular antiviral response,as evidenced by the increased expression of viral genes and more severe cytopathic efects(CPE)in cells infected with spring viremia of carp virus(SVCV).These results indicated that LcMFN2 inhibited type I IFN response by degrading MAVS,suggesting its negative regulatory role in cellular antiviral response.Therefore,our study sheds a new light on the regulatory mechanisms of the cellular antiviral response in teleosts.展开更多
Porcine reproductive and respiratory syndrome (PRRS) is a devastating disease caused by the PRRS virus. The MontanideTM class of flexible polymeric adjuvants has recently been shown to enhance protective immunity agai...Porcine reproductive and respiratory syndrome (PRRS) is a devastating disease caused by the PRRS virus. The MontanideTM class of flexible polymeric adjuvants has recently been shown to enhance protective immunity against PRRSV infection in piglets when used in combination with PRRS modified live vaccines (MLV). In this study, we explored the efficacy and immunological mechanisms of protection of MontanideTM Gel01 ST (Gel01) adjuvanted modified live PRRSV vaccine in pigs challenged with two genetically distinct strains of PRRSV. Gel01-MLV reduced lymph node pathology scores in pigs challenged with VR-2332 (parental strain of MLV vaccine) but not that in pigs challenged with MN184A (heterologous strain), when compared to that in pigs vaccinated with un-adjuvanted MLV. Pigs vaccinated with Gel01-MLV had higher levels of PRRS-specific antibodies, as measured by IDEXX ELISA and virus neutralizing antibodies, after vaccination and VR-2332 challenge. In addition, pigs vaccinated with Gel01-MLV had decreased levels of IFN-γ, IL-10, and T-regulatory lymphocytes in the blood as compared to that in pigs vaccinated with MLV alone. Interestingly, we found that addition of Gel01 did not change the profile of other T lymphocyte populations after PRRSV challenge. These results demonstrate that the MLV adjuvanted with Gel01 provides enhanced protection against homologous PRRSV infection, possibly by regulating the production of PRRSV-specific antibodies and cytokines involved in the development of T-regulatory cells. Thus, Gel01 ST is a promising adjuvant that can be formulated with PRRSV MLV vaccines to reduce disease severity and tissue damage caused by PRRSV infection in pigs.展开更多
Objective： The combination of interferon （IFN） and ribavirin （RBV） is the standard therapy for hepatitis C virus （HCV） infection. HCV genotype 2a has proved more amenable to the therapy, but its efficacy is yet...Objective： The combination of interferon （IFN） and ribavirin （RBV） is the standard therapy for hepatitis C virus （HCV） infection. HCV genotype 2a has proved more amenable to the therapy, but its efficacy is yet fimited. This study aimed to investigate the mechanism of the poor response in a case ofHCV genotype 2a infection. Methods： We analyzed dynamic change of HCV RNA from a patient, infected with HCV genotype 2a, showing a poor virological response to 1FN/RBV as judged 12 weeks after initiation of the therapy by HCV clone sequencing. Then we constructed subgenomic Japanese fulminant hepatitis-1 （JFH1） replicon and different chimeric replicons with humanized Gaussia luciferase gene. The chimeric replicons were derived from subgenomic JFH1 replicon, in which the NS5A region was replaced by the patient＇s sequence from the pre/post- treatment, and the chimeric replicons＇ susceptibility to IFN were evaluated by relative Gausia Luciferase activity. Results： The pretreatment HCV sequences appeared almost uniform, and the quasispecies variation was further more simplified after 12 weeks of therapy. Besides, the quasispecies variation seemed to be more diversified in the NS5A, relatively, a region crucial for IFN response, and each of chimeric replicons exhibited distinct response to IFN. Conclusions： During the course of the chronic infection, HCV population seems to be adapted to the patient＇s immunological system, and further to be selected by combination of 1FN/RBV therapy, indicating quasispecies may completely eliminated by addition of other drugs with targets different from those of IFN. In addition, each different response of chimeric replicon to IFN is most likely related to amino acid changes in or near the IFN-sensitivity determining region （ISDR） of NSSA during chronic infection and IFN/RBV therapy.展开更多
HBV is considered as a“stealth”virus that does not invoke interferon(IFN)responses;however,the mechanisms by which HBV bypasses innate immune recognition are poorly understood.In this study,we identified adenosine d...HBV is considered as a“stealth”virus that does not invoke interferon(IFN)responses;however,the mechanisms by which HBV bypasses innate immune recognition are poorly understood.In this study,we identified adenosine deaminases acting on RNA 1(ADAR1),which is a key factor in HBV evasion from IFN responses in hepatocytes.Mechanically,ADAR1 interacted with HBV RNAs and deaminated adenosine(A)to generate inosine(I),which disrupted host immune recognition and thus promoted HBV replication.Loss of ADAR1 or its deficient deaminase activity promoted IFN responses and inhibited HBV replication in hepatocytes,and blocking the IFN signaling pathways released the inhibition of HBV replication caused by ADAR1 deficiency.Notably,the HBV X protein(HBx)transcriptionally promoted ADAR1 expression to increase the threshold required to trigger intrinsic immune activation,which in turn enhanced HBV escape from immune recognition,leading to persistent infection.Supplementation with 8-azaadenosine,an ADAR1 inhibitor,efficiently enhanced liver immune activation to promote HBV clearance in vivo and in vitro.Taken together,our results delineate a molecular mechanism by which HBx promotes ADAR1-derived HBV immune escape and suggest a targeted therapeutic intervention for HBV infection.展开更多
文摘目的探讨白细胞介素10(interleukin-10,IL-10)、interferon-γ(IFN-γ)在腺样体肥大(adenoidal hypertrophy,AH)导致分泌性中耳炎(otitis media with effusion,OME)发生发展中的作用。方法以2015年5月~2016年12月期间完成腺样体切除术的72例腺样体肥大患儿为研究对象,其中单纯腺样体肥大42例(单纯AH组),伴OME的腺样体肥大30例(AH伴OME组),以20例同期住院行甲状舌管囊肿切除或者耳前瘘管切除手术且腺样体正常大小患儿做对照组,采用ELISA方法检测所有研究对象腺样体组织和外周血中IL-10、IFN-γ的表达水平,比较各组结果。结果AH伴OME组、单纯AH组腺样体组织中的IL-10浓度分别为125.95±21.74、51.62±18.79 pg/l,明显高于正常对照组(27.48±10.52 pg/L)(P<0.05),AH伴OME组高于单纯AH组,差异也有统计学意义(P<0.05);AH伴OME组、单纯AH组腺样体组织的IFN-γ浓度分别为622.35±72.14和610.27±45.18 pg/l,两组间差异无统计学意义(P>0.05),但高于正常对照组(341.18±32.11 pg/l),差异有统计学意义(P<0.05);AH伴OME组IFN-γ/IL-10比值明显低于AH组和正常对照组(P<0.01);三组间外周血中IL-10、IFN-γ以及IFN-γ/IL-10值差异无统计学意义(P>0.05)。结论AH伴OME组患儿腺样体组织中IFN-γ/IL-10比值下降,致Th1/Th2失衡,推测以IFN-γ/IL-10比值下降为代表的TH2优势可能是腺样体肥大导致分泌性中耳炎的发病机制之一。
基金This work was supported in whole or in part by the National Natural Science Foundation of China(82172272,31970148 and 82222367)the Key Research and Development Program of Shaanxi(2021ZDLSF01-05 and 2021ZDLSF01-02).
文摘Hantaan virus(HTNV)is a rodent-borne virus that causes hemorrhagic fever with renal syndrome(HFRS),resulting in a high mortality rate of 15%.Interferons(IFNs)play a critical role in the anti-hantaviral immune response,and IFN pretreatment efficiently restricts HTNV infection by triggering the expression of a series of IFNstimulated genes(ISGs)through the Janus kinase-signal transducer and activator of transcription 1(JAK-STAT)pathway.However,the tremendous amount of IFNs produced during late infection could not restrain HTNV replication,and the mechanism remains unclear.Here,we demonstrated that receptor-interacting protein kinase 3(RIPK3),a crucial molecule that mediates necroptosis,was activated by HTNV and contributed to hantavirus evasion of IFN responses by inhibiting STAT1 phosphorylation.RNA-seq analysis revealed the upregulation of multiple cell death-related genes after HTNV infection,with RIPK3 identified as a key modulator of viral replication.RIPK3 ablation significantly enhanced ISGs expression and restrained HTNV replication,without affecting the expression of pattern recognition receptors(PRRs)or the production of type I IFNs.Conversely,exogenously expressed RIPK3 compromised the host's antiviral response and facilitated HTNV replication.RIPK3^(-/-)mice also maintained a robust ability to clear HTNV with enhanced innate immune responses.Mechanistically,we found that RIPK3 could bind STAT1 and inhibit STAT1 phosphorylation dependent on the protein kinase domain(PKD)of RIPK3 but not its kinase activity.Overall,these observations demonstrated a noncanonical function of RIPK3 during viral infection and have elucidated a novel host innate immunity evasion strategy utilized by HTNV.
文摘为检测SLE患者外周血γ干扰素诱导蛋白10(interferon gamma-induced protein 10,IP-10)的表达情况并探索其临床意义及调控机制,采集上海交通大学医学院附属仁济医院SLE患者和健康体检者外周血,ELISA检测血清中IP-10和IFN-α水平。结果显示,IP-10在SLE患者血清中的水平明显高于对照者(P<0.05);同时根据SLEDAI评分将患者分为无活动组(0~5分)、低活动度组(5~10分)和高活动度组(10分以上)后,发现SLE患者血清中IP-10水平与SLEDAI评分呈明显正相关(r=0.5703,P<0.05)。FACS检测外周血IP-10+细胞类型,发现高活动度组中IP-10+B细胞、NK细胞和单核细胞百分比明显高于低活动度组和正常对照组。用IFN-α刺激SLE患者和健康人PBMC,发现两组培养上清中IP-10水平明显高于未刺激组,但两组间差异无统计学意义(P>0.05);其中IP-10+B细胞百分比也显著升高,并且患者组升高更明显(均P<0.05)。上述结果提示SLE患者中B细胞在IFN-α作用下直接活化产生抗体的同时,也可通过分泌IP-10参与病理性炎症反应,这揭示了B细胞参与SLE发生发展的新机制。
文摘Cytokines are involved in directing the activation of natural killer （NK） cells. NK cells are involved in the recognition of cells that have been altered; thus they do not recognize specific insults to the host, but when activated, are capable of destroying infected cells directly, as well as promoting the recruitment and response of the other components of the immune system by the release of cytokines and chemokines. It is these properties that have made NK cells a critical part of innate immunity and adaptive immunity, and they play a principal role linking innate and adaptive immunity by the recruitment of an adaptive immune response to an innate immune reaction.
基金supported by grants from the National Key R&D Program of China(2022YFF1000302)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA24010308)+1 种基金the National Natural Science Foundation(31972826 and 32102838)the Freshwater Ecology and Biotechnology Laboratory(2019FBZ04).
文摘Vertebrate interferon(IFN)expression is fine-tuned in order to avoid excessive tissue injury under normal conditions and during virus infection.FinTRIM(fish novel TRIM,FTR)proteins are reported to regulate the fish IFN response.Here,we identify a novel finTRIM gene from yellow catfish(Pelteobagrus fulvidraco),which is sequentially named PfFTR100 according to the nomenclature rule in zebrafish.Genome-wide analyses reveal that FTR100 is unique to Otomorpha fish,with a single copy in spite of additional genome duplication in some fish species.Considering that few of the 99 finTRIM genes identified in zebrafish are conserved in main fish branches and most,such as FTR100,are unique to distinct branches due to lineage-specific expansion of finTRIM genes,we develop a nomenclature for newly cloned finTRIM genes from different fish species.PfFTR100 mRNA is not induced by virus infection,with a relatively high expression level comparable to that of cellular IFN and some IFN-stimulated genes(ISGs)in virally-infected tissues.However,ectopically-expressed PfFTR100 protein is attenuated in virally-infected cells through the proteasomal-dependent pathway.Overexpression of PfFTR100 promotes SVCV replication by downregulating the constitutive and inducible IFN response via a mechanism by which PfFTR100 targets IRF3 and IRF7 to attenuate their mRNA levels rather than their protein levels.Our results indicate that yellow catfish FTR100 is essential for homeostatic regulation of fish tonic IFN response.
基金This work was supported by National Key Research and Development Program of China under Grant No.2022YFD2401001National Natural Science Foundation of China under Grant No.U1905204+2 种基金China Agriculture Research System of MOF and MARA under Grant No.CARS-47Fujian Science and Technology Department under Grant No.2021N5008Institute of Oceanology of Fuzhou(2021F02).
文摘In mammals,mitofusin 2(MFN2)is involved in mitochondrial fusion,and suppresses the virus-induced RIG-I-like receptor(RLR)signaling pathway.However,little is known about the function of MFN2 in non-mammalian species.In the present study,we cloned an MFN2 ortholog(LcMFN2)in large yellow croaker(Larimichthys crocea).Phylogenetic analysis showed that MFN2 emerged after the divergence of amphioxus and vertebrates.The protein sequences of MFN2 were well conserved from fsh to mammals.LcMFN2 was expressed in all the tissues/organs examined at diferent levels,and its expression was upregulated in response to poly(I:C)stimulation.Overexpression of LcMFN2 inhibited MAVS-induced type I interferon(IFN)promoter activation and antiviral gene expression.In contrast,knockdown of endogenous LcMFN2 enhanced poly(I:C)induced production of type I IFNs.Additionally,LcMFN2 enhanced K48-linked polyubiquitination of MAVS,promoting its degradation.Also,overexpression of LcMFN2 impaired the cellular antiviral response,as evidenced by the increased expression of viral genes and more severe cytopathic efects(CPE)in cells infected with spring viremia of carp virus(SVCV).These results indicated that LcMFN2 inhibited type I IFN response by degrading MAVS,suggesting its negative regulatory role in cellular antiviral response.Therefore,our study sheds a new light on the regulatory mechanisms of the cellular antiviral response in teleosts.
文摘Porcine reproductive and respiratory syndrome (PRRS) is a devastating disease caused by the PRRS virus. The MontanideTM class of flexible polymeric adjuvants has recently been shown to enhance protective immunity against PRRSV infection in piglets when used in combination with PRRS modified live vaccines (MLV). In this study, we explored the efficacy and immunological mechanisms of protection of MontanideTM Gel01 ST (Gel01) adjuvanted modified live PRRSV vaccine in pigs challenged with two genetically distinct strains of PRRSV. Gel01-MLV reduced lymph node pathology scores in pigs challenged with VR-2332 (parental strain of MLV vaccine) but not that in pigs challenged with MN184A (heterologous strain), when compared to that in pigs vaccinated with un-adjuvanted MLV. Pigs vaccinated with Gel01-MLV had higher levels of PRRS-specific antibodies, as measured by IDEXX ELISA and virus neutralizing antibodies, after vaccination and VR-2332 challenge. In addition, pigs vaccinated with Gel01-MLV had decreased levels of IFN-γ, IL-10, and T-regulatory lymphocytes in the blood as compared to that in pigs vaccinated with MLV alone. Interestingly, we found that addition of Gel01 did not change the profile of other T lymphocyte populations after PRRSV challenge. These results demonstrate that the MLV adjuvanted with Gel01 provides enhanced protection against homologous PRRSV infection, possibly by regulating the production of PRRSV-specific antibodies and cytokines involved in the development of T-regulatory cells. Thus, Gel01 ST is a promising adjuvant that can be formulated with PRRSV MLV vaccines to reduce disease severity and tissue damage caused by PRRSV infection in pigs.
文摘Objective： The combination of interferon （IFN） and ribavirin （RBV） is the standard therapy for hepatitis C virus （HCV） infection. HCV genotype 2a has proved more amenable to the therapy, but its efficacy is yet fimited. This study aimed to investigate the mechanism of the poor response in a case ofHCV genotype 2a infection. Methods： We analyzed dynamic change of HCV RNA from a patient, infected with HCV genotype 2a, showing a poor virological response to 1FN/RBV as judged 12 weeks after initiation of the therapy by HCV clone sequencing. Then we constructed subgenomic Japanese fulminant hepatitis-1 （JFH1） replicon and different chimeric replicons with humanized Gaussia luciferase gene. The chimeric replicons were derived from subgenomic JFH1 replicon, in which the NS5A region was replaced by the patient＇s sequence from the pre/post- treatment, and the chimeric replicons＇ susceptibility to IFN were evaluated by relative Gausia Luciferase activity. Results： The pretreatment HCV sequences appeared almost uniform, and the quasispecies variation was further more simplified after 12 weeks of therapy. Besides, the quasispecies variation seemed to be more diversified in the NS5A, relatively, a region crucial for IFN response, and each of chimeric replicons exhibited distinct response to IFN. Conclusions： During the course of the chronic infection, HCV population seems to be adapted to the patient＇s immunological system, and further to be selected by combination of 1FN/RBV therapy, indicating quasispecies may completely eliminated by addition of other drugs with targets different from those of IFN. In addition, each different response of chimeric replicon to IFN is most likely related to amino acid changes in or near the IFN-sensitivity determining region （ISDR） of NSSA during chronic infection and IFN/RBV therapy.
基金This work was supported by grants from the National Science Foundation of China(Key program 81830017,Nos.81672425 and 81902051)the National Natural Science Fund for Outstanding Youth Fund(81425012)+3 种基金Taishan Scholarship(No.tspd20181201)Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong,Key Research and Development Program of Shandong(2019GSF108238)the National Key Research and Development Program(2018YFE0126500 and 2016YFE0127000)China Mobility Grant jointly funded by the National Science Foundation of China and the Swedish Foundation for International Cooperation in Research and Higher Education(STINT),and China Postdoctoral Science Foundation(No.2018 M30782).
文摘HBV is considered as a“stealth”virus that does not invoke interferon(IFN)responses;however,the mechanisms by which HBV bypasses innate immune recognition are poorly understood.In this study,we identified adenosine deaminases acting on RNA 1(ADAR1),which is a key factor in HBV evasion from IFN responses in hepatocytes.Mechanically,ADAR1 interacted with HBV RNAs and deaminated adenosine(A)to generate inosine(I),which disrupted host immune recognition and thus promoted HBV replication.Loss of ADAR1 or its deficient deaminase activity promoted IFN responses and inhibited HBV replication in hepatocytes,and blocking the IFN signaling pathways released the inhibition of HBV replication caused by ADAR1 deficiency.Notably,the HBV X protein(HBx)transcriptionally promoted ADAR1 expression to increase the threshold required to trigger intrinsic immune activation,which in turn enhanced HBV escape from immune recognition,leading to persistent infection.Supplementation with 8-azaadenosine,an ADAR1 inhibitor,efficiently enhanced liver immune activation to promote HBV clearance in vivo and in vitro.Taken together,our results delineate a molecular mechanism by which HBx promotes ADAR1-derived HBV immune escape and suggest a targeted therapeutic intervention for HBV infection.
