Background The extracellular release of the danger signal high mobility group box-1 （HMGB1） has been implicated in the pathogenesis and outcomes of sepsis. Understanding the mechanisms responsible for HMGB1 release ...Background The extracellular release of the danger signal high mobility group box-1 （HMGB1） has been implicated in the pathogenesis and outcomes of sepsis. Understanding the mechanisms responsible for HMGB1 release can lead to the identification of targets that may inhibit this process. The transcription factor interferon regulatory factor-1 （IRF-1） is an important mediator of innate immune responses and has been shown to participate in mortality associated with endotoxemia; however, its role in mediating the release of HMGB1 in these settings is unknown. Methods Male IRF-1 knockout （KO） and age matched C57BL/6 wild type （WT） mice were given intraperitoneal （IP） injections of lipopolysaccharide （LPS）. In some experiments, 96 hours survival rates were observed. In other experiments, mice were sacrificed 12 hours after LPS administration and sera were harvested for future analysis. In in vitro study, RAW 264.7 murine monocyte/macrophage-like cells or primary peritoneal macrophage obtained from IRF-1 KO and WT mice were cultured for LPS mediated HMGB1 release analysis. And the mechanism for HMGB1 release was analyzed by immune-precipitation. Results IRF-1 KO mice experienced less mortality, and released less systemic HMGB1 compared to their WT counterparts. Exogenous administration of recombinant HMGB1 to IRF-1 KO mice returned the mortality rate to that seen originally in IRF-1 WT mice. Using cultures of peritoneal macrophages or RAW264.7 cells, in vitro LPS stimulation induced the release of HMGB1 in an IRF-1 dependent manner. And the janus associated kinase （JAK）-IRF-1 signal pathway appeared to participate in the signaling mechanisms of LPS-induced HMGB1 release by mediating acetylation of HMGBI. Conclusion IRF-1 plays a role in LPS induced release of HMGB1 and therefore may serve as a novel target in sepsis~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
Interferon Regulatory Factor-2 (IRF-2) belongs to IRF family, was identified as a mammalian transcription factor involved in Interferon beta (IFNβ) gene regulation. Besides that IRF-2 is involved in immunomodulation,...Interferon Regulatory Factor-2 (IRF-2) belongs to IRF family, was identified as a mammalian transcription factor involved in Interferon beta (IFNβ) gene regulation. Besides that IRF-2 is involved in immunomodulation, hematopoietic differentiation, cell cycle regulation and oncogenesis. We have done molecular sub-cloning and expression of recombinant murine IRF-2 as GST (Glutathione-S-Transferase)- IRF-2 fusion protein in E. coli/XL-1blue cells. Recombinant IRF-2 with GST moiety at N-terminus expressed as GST-IRF-2 (~66 kd) in E. coli along with different low molecular mass degradation products revealed approximately 30, 42, 60 and 62 kd by SDS-PAGE and Western blot, respectively. We further confirm that degradation takes place at C-terminus of the fusion protein not at N-terminus as anti-GST antibody was detecting all bands in the immunoblot. The recombinant IRF-2 was biologically active along with their degradation products in terms of their DNA binding activity as assessed by Electrophoretically Mobility Shift Assay (EMSA). We observed three different molecular mass DNA/protein complexes (1 - 3) with Virus Response Element (VRE) derived from human Interferon IFNβ gene and five different molecular mass complexes (1 - 5) with IRF-E motif (GAAAGT)4 in EMSA gel. GST only expressed from empty vector did not bind to these DNA elements. To confirm that the binding is specific, all complexes were competed out completely when challenged with 100-X fold molar excess of IRF-E oligo under cold competition. It means degradation products along with full-length protein are able to interact with VREβ as well as IRF-E motif. This means degradation products may regulate the target gene (s) activation/repression via interacting with VRE/IRF-E.展开更多
AIM: To elucidate the molecular and cellular features responsible for the increase of regulatory T cells (Tregs) in gastric cancer. METHODS: The frequencies of CD4 + Foxp3 + Tregs and the level of transforming growth ...AIM: To elucidate the molecular and cellular features responsible for the increase of regulatory T cells (Tregs) in gastric cancer. METHODS: The frequencies of CD4 + Foxp3 + Tregs and the level of transforming growth factor-β1 (TGF-β1) were analyzed from 56 patients with gastric cancer byflow cytometry and enzyme-linked immunosorbent assay respectively. Foxp3 gene expression was analyzed by real-time polymerase chain reaction. The gastric cancer microenvironment was modeled by establishing the coculture of gastric cancer cell line, MGC-803, with sorting CD4 + T cells. The normal gastric mucosa cell line, GES-1, was used as the control. The production of TGF-β1 was detected in supernatant of MGC and GES-1. The carboxyfluorescein diacetatesuccinimidyl ester (CFSE) dilution assay was performed to evaluate the proliferation characteristics of induced Tregs. Neutralizing anti-TGF-β1 antibody was added to the co-culture system for neutralization experiments. RESULTS: The level of serum TGF-β1 in gastric cancer patients (15.1 ± 5.5 ng/mL) was significantly higher than that of the genderand age-matched healthy controls (10.3 ± 3.4 ng/mL) (P < 0.05). Furthermore, the higher TGF-β1 level correlated with the increased population of CD4 + Foxp3 + Tregs in advanced gastric cancer (r = 0.576, P < 0.05). A significant higher frequency of CD4 + Foxp3 + Tregs was observed in PBMCs cultured with the supernatant of MGC than GES-1 (10.6% ± 0.6% vs 8.7% ± 0.7%, P < 0.05). Moreover, using the purified CD4 + CD25 T cells, we confirmed that the increased Tregs were mainly induced from the conversation of CD4 + CD25 naive T cells, and induced Tregs were functional and able to suppress the proliferation of effector T cells. Finally, we demonstrated that gastric cancer cells induced the increased CD4 + Foxp3 + Tregs via producing TGF-β1. Gastric cancer cells upregulated the production of TGF-β1 and blockade of TGF-β1 partly abrogated Tregs phenotype. CONCLUSION: Gastric cancer cell can induce Tregs development via producing TGF-β1, by which the existence of cross-talk between the tumor and immune cells might regulate anti-tumor immune responses.展开更多
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...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.展开更多
Heart diseases are the main cause of mortality in Mexico, being coronary </span><span style="font-family:Verdana;">heart disease the most frequent in the country. Its high prevalence makes i...Heart diseases are the main cause of mortality in Mexico, being coronary </span><span style="font-family:Verdana;">heart disease the most frequent in the country. Its high prevalence makes important </span><span style="font-family:Verdana;">the study of the pathophysiology and the search for prognostic </span><span style="font-family:Verdana;">factors. Different genes and polymorphisms promote atherogenesis and coronary artery disease, they affect inflammatory and vascular pathological processes. </span><span style="font-family:Verdana;">Interferon regulatory factor 5 (IRF5) is associated with coronary heart disease, it promotes chronic inflammation and cytokines release;it could trigger immune reactions and its activating receptors express in the vascular endothelium. Besides, polymorphisms in the renin-angiotensin-aldosterone system (RAAS) are implied with coronary disease, they are found in angiotensinogen (AGT), angiotensin II type 1 receptor (AT1R), angiotensin II type 2 receptor (AT2R), and angiotensin-converting enzyme (ACE) genes. These genetic polymorphisms are associated with a prothrombotic state, endothelial dysfunction, and immune activation. Multiple experimental studies showed that chronic activation of RAAS and chronic expression of IRF5 generates an environment prone to the development of atherosclerosis, and autoimmune and cardiovascular diseases. Studying these specific genes and their relationship with coronary heart disease will allow a better understanding of the pathological process and possibly the quest for new treatments.展开更多
目的研究丁酸钠(NaB)抑制鼻咽癌细胞CNE2吲哚胺-吡咯2,3-双加氧酶(IDO)表达从而解除肿瘤免疫耐受的分子机制。方法体外培养人鼻咽癌上皮细胞CNE2,采用NaB和(或)IFN-γ处理CNE2细胞;免疫印迹检测CNE2细胞IDO的表达情况;RT-PCR检测JAK/STA...目的研究丁酸钠(NaB)抑制鼻咽癌细胞CNE2吲哚胺-吡咯2,3-双加氧酶(IDO)表达从而解除肿瘤免疫耐受的分子机制。方法体外培养人鼻咽癌上皮细胞CNE2,采用NaB和(或)IFN-γ处理CNE2细胞;免疫印迹检测CNE2细胞IDO的表达情况;RT-PCR检测JAK/STAT的细胞因子信号抑制因子1(SOCS1)和SOCS3的转录水平;Real time PCR检测CNE2细胞干扰素调节因子-1(IRF-1)的转录情况。结果在NaB作用下,CNE2细胞内IDO的表达减少,并且IFN-γ诱导的IDO表达也被显著抑制;SOCS1和SOCS3的转录水平未见改变;而IFN-γ诱导的IRF1转录受到NaB的显著抑制。结论 NaB抑制IFN-γ诱导的IDO表达,不是通过增加SOCS1和SOCS3的转录,而可能是通过下调IRF-1,抑制IFN-γ诱导的IDO表达。展开更多
文摘Background The extracellular release of the danger signal high mobility group box-1 （HMGB1） has been implicated in the pathogenesis and outcomes of sepsis. Understanding the mechanisms responsible for HMGB1 release can lead to the identification of targets that may inhibit this process. The transcription factor interferon regulatory factor-1 （IRF-1） is an important mediator of innate immune responses and has been shown to participate in mortality associated with endotoxemia; however, its role in mediating the release of HMGB1 in these settings is unknown. Methods Male IRF-1 knockout （KO） and age matched C57BL/6 wild type （WT） mice were given intraperitoneal （IP） injections of lipopolysaccharide （LPS）. In some experiments, 96 hours survival rates were observed. In other experiments, mice were sacrificed 12 hours after LPS administration and sera were harvested for future analysis. In in vitro study, RAW 264.7 murine monocyte/macrophage-like cells or primary peritoneal macrophage obtained from IRF-1 KO and WT mice were cultured for LPS mediated HMGB1 release analysis. And the mechanism for HMGB1 release was analyzed by immune-precipitation. Results IRF-1 KO mice experienced less mortality, and released less systemic HMGB1 compared to their WT counterparts. Exogenous administration of recombinant HMGB1 to IRF-1 KO mice returned the mortality rate to that seen originally in IRF-1 WT mice. Using cultures of peritoneal macrophages or RAW264.7 cells, in vitro LPS stimulation induced the release of HMGB1 in an IRF-1 dependent manner. And the janus associated kinase （JAK）-IRF-1 signal pathway appeared to participate in the signaling mechanisms of LPS-induced HMGB1 release by mediating acetylation of HMGBI. Conclusion IRF-1 plays a role in LPS induced release of HMGB1 and therefore may serve as a novel target in sepsis~
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.
文摘Interferon Regulatory Factor-2 (IRF-2) belongs to IRF family, was identified as a mammalian transcription factor involved in Interferon beta (IFNβ) gene regulation. Besides that IRF-2 is involved in immunomodulation, hematopoietic differentiation, cell cycle regulation and oncogenesis. We have done molecular sub-cloning and expression of recombinant murine IRF-2 as GST (Glutathione-S-Transferase)- IRF-2 fusion protein in E. coli/XL-1blue cells. Recombinant IRF-2 with GST moiety at N-terminus expressed as GST-IRF-2 (~66 kd) in E. coli along with different low molecular mass degradation products revealed approximately 30, 42, 60 and 62 kd by SDS-PAGE and Western blot, respectively. We further confirm that degradation takes place at C-terminus of the fusion protein not at N-terminus as anti-GST antibody was detecting all bands in the immunoblot. The recombinant IRF-2 was biologically active along with their degradation products in terms of their DNA binding activity as assessed by Electrophoretically Mobility Shift Assay (EMSA). We observed three different molecular mass DNA/protein complexes (1 - 3) with Virus Response Element (VRE) derived from human Interferon IFNβ gene and five different molecular mass complexes (1 - 5) with IRF-E motif (GAAAGT)4 in EMSA gel. GST only expressed from empty vector did not bind to these DNA elements. To confirm that the binding is specific, all complexes were competed out completely when challenged with 100-X fold molar excess of IRF-E oligo under cold competition. It means degradation products along with full-length protein are able to interact with VREβ as well as IRF-E motif. This means degradation products may regulate the target gene (s) activation/repression via interacting with VRE/IRF-E.
基金Supported by Shanghai Municipal Natural Science Foundation, No. 10ZR1420000National Natural Science Foundation of China, No. 81072009
文摘AIM: To elucidate the molecular and cellular features responsible for the increase of regulatory T cells (Tregs) in gastric cancer. METHODS: The frequencies of CD4 + Foxp3 + Tregs and the level of transforming growth factor-β1 (TGF-β1) were analyzed from 56 patients with gastric cancer byflow cytometry and enzyme-linked immunosorbent assay respectively. Foxp3 gene expression was analyzed by real-time polymerase chain reaction. The gastric cancer microenvironment was modeled by establishing the coculture of gastric cancer cell line, MGC-803, with sorting CD4 + T cells. The normal gastric mucosa cell line, GES-1, was used as the control. The production of TGF-β1 was detected in supernatant of MGC and GES-1. The carboxyfluorescein diacetatesuccinimidyl ester (CFSE) dilution assay was performed to evaluate the proliferation characteristics of induced Tregs. Neutralizing anti-TGF-β1 antibody was added to the co-culture system for neutralization experiments. RESULTS: The level of serum TGF-β1 in gastric cancer patients (15.1 ± 5.5 ng/mL) was significantly higher than that of the genderand age-matched healthy controls (10.3 ± 3.4 ng/mL) (P < 0.05). Furthermore, the higher TGF-β1 level correlated with the increased population of CD4 + Foxp3 + Tregs in advanced gastric cancer (r = 0.576, P < 0.05). A significant higher frequency of CD4 + Foxp3 + Tregs was observed in PBMCs cultured with the supernatant of MGC than GES-1 (10.6% ± 0.6% vs 8.7% ± 0.7%, P < 0.05). Moreover, using the purified CD4 + CD25 T cells, we confirmed that the increased Tregs were mainly induced from the conversation of CD4 + CD25 naive T cells, and induced Tregs were functional and able to suppress the proliferation of effector T cells. Finally, we demonstrated that gastric cancer cells induced the increased CD4 + Foxp3 + Tregs via producing TGF-β1. Gastric cancer cells upregulated the production of TGF-β1 and blockade of TGF-β1 partly abrogated Tregs phenotype. CONCLUSION: Gastric cancer cell can induce Tregs development via producing TGF-β1, by which the existence of cross-talk between the tumor and immune cells might regulate anti-tumor immune responses.
基金Supported by Grants of The Chinese State Basic Research, No.2009CB522504National Mega Projects for Infectious Diseases, No. 2008ZX10203
文摘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.
文摘Heart diseases are the main cause of mortality in Mexico, being coronary </span><span style="font-family:Verdana;">heart disease the most frequent in the country. Its high prevalence makes important </span><span style="font-family:Verdana;">the study of the pathophysiology and the search for prognostic </span><span style="font-family:Verdana;">factors. Different genes and polymorphisms promote atherogenesis and coronary artery disease, they affect inflammatory and vascular pathological processes. </span><span style="font-family:Verdana;">Interferon regulatory factor 5 (IRF5) is associated with coronary heart disease, it promotes chronic inflammation and cytokines release;it could trigger immune reactions and its activating receptors express in the vascular endothelium. Besides, polymorphisms in the renin-angiotensin-aldosterone system (RAAS) are implied with coronary disease, they are found in angiotensinogen (AGT), angiotensin II type 1 receptor (AT1R), angiotensin II type 2 receptor (AT2R), and angiotensin-converting enzyme (ACE) genes. These genetic polymorphisms are associated with a prothrombotic state, endothelial dysfunction, and immune activation. Multiple experimental studies showed that chronic activation of RAAS and chronic expression of IRF5 generates an environment prone to the development of atherosclerosis, and autoimmune and cardiovascular diseases. Studying these specific genes and their relationship with coronary heart disease will allow a better understanding of the pathological process and possibly the quest for new treatments.
文摘目的研究丁酸钠(NaB)抑制鼻咽癌细胞CNE2吲哚胺-吡咯2,3-双加氧酶(IDO)表达从而解除肿瘤免疫耐受的分子机制。方法体外培养人鼻咽癌上皮细胞CNE2,采用NaB和(或)IFN-γ处理CNE2细胞;免疫印迹检测CNE2细胞IDO的表达情况;RT-PCR检测JAK/STAT的细胞因子信号抑制因子1(SOCS1)和SOCS3的转录水平;Real time PCR检测CNE2细胞干扰素调节因子-1(IRF-1)的转录情况。结果在NaB作用下,CNE2细胞内IDO的表达减少,并且IFN-γ诱导的IDO表达也被显著抑制;SOCS1和SOCS3的转录水平未见改变;而IFN-γ诱导的IRF1转录受到NaB的显著抑制。结论 NaB抑制IFN-γ诱导的IDO表达,不是通过增加SOCS1和SOCS3的转录,而可能是通过下调IRF-1,抑制IFN-γ诱导的IDO表达。
