目的:探讨鞘内注射小胶质细胞干扰素调节因子8(interferon regulatory factor 8,IRF8)反义寡核苷酸(oligodeoxynucleotide,ODN)对大鼠慢性坐骨神经缩窄损伤(chronic constriction injury of sciatic nerve,CCI)模型疼痛行为的影响。方法...目的:探讨鞘内注射小胶质细胞干扰素调节因子8(interferon regulatory factor 8,IRF8)反义寡核苷酸(oligodeoxynucleotide,ODN)对大鼠慢性坐骨神经缩窄损伤(chronic constriction injury of sciatic nerve,CCI)模型疼痛行为的影响。方法:雄性SD大鼠40只随机分为4组:Sham组、AS组、MM组、NS组,每组10只。除Sham组外,其他三组均鞘内置管并制备CCI模型,AS组、MM组、NS组依次于CCI后12 h鞘内注射IRF8反义/错义ODN、等体积生理盐水,1次/d,连续6 d。制模前测量各组大鼠的基础阈值,制模后1、3、5、7、10、12、14 d对大鼠进行疼痛行为测定。制模后7、14 d western blot检测IRF8、离子钙接合蛋白Iba1表达。结果:与Sham组比较,NS组、MM组大鼠神经损伤后右后爪机械痛阈和热痛阈均显著降低(P<0.05),脊髓IRF8、Iba1蛋白表达显著增强(P<0.05)。AS组于CCI后第10 d起右足机械痛阈和热痛阈下降,但仍高于MM组、NS组(P<0.05)。CCI后第7、14 d IRF8、Iba1蛋白表达,AS组较MM组、NS组显著减弱(P<0.05),但仍强于Sham组(P<0.05)。AS组第14 d IRF8、Iba1蛋白表达较第7 d增强(P<0.05)。结论:经鞘内注射IRF8反义寡核苷酸可抑制脊髓内IRF8表达和小胶质细胞活化而缓解CCI大鼠神经病理性疼痛。展开更多
Objective:To assess the effects of nebulized inhaled Mycobacterium vaccae on allergic airway inflammation,airway hyperresponsiveness,and Th1/Th2 cell imbalance in mice with ovalbumin(OVA)-induced asthma.Methods:Mice r...Objective:To assess the effects of nebulized inhaled Mycobacterium vaccae on allergic airway inflammation,airway hyperresponsiveness,and Th1/Th2 cell imbalance in mice with ovalbumin(OVA)-induced asthma.Methods:Mice received OVA sensitization and challenge for establishment of the asthmatic model.For intervention,mice received Mycobacterium vaccae nebulization once every other day from the first day of sensitization to the day before challenge.After challenge,pulmonary histological analysis and airway responsiveness measurement were performed.In addition,Th1/Th2 cytokines and OVA-specific IgE levels in bronchoalveolar lavage fluid were measured by ELISA.Th1/Th2 subset ratios and the expression of interferon-regulatory factor 4(IRF4),IRF8 and Toll-like receptor 4(TLR4)in dendritic cells were evaluated by flow cytometry.Results:Severe inflammatory infiltration and airway hyperresponsiveness were observed in OVA-induced asthmatic mice.Asthmatic mice showed higher Th2 cytokine concentration and increased percentage of Th2 cells,along with lower Th1 cytokine concentration and reduced percentage of Th1 cells compared with the normal control.Moreover,an imbalance of IRF4^(+)and IRF8^(+)in dendritic cells was found in asthmatic mice.Nebulized inhaled Mycobacterium vaccae reduced airway hyperresponsiveness and inflammation in OVA-induced asthmatic mice.In addition,nebulized inhaled Mycobacterium vaccae enhanced TLR4 and IRF8 expression,and alleviated the imbalance of Th1/Th2 as well as IRF4^(+)and IRF8^(+)in dendritic cells.Conclusions:Nebulized inhaled Mycobacterium vaccae protects against asthma by alleviating the imbalance of Th1/Th2 and IRF4/IRF8 in OVA-induced asthmatic mice.展开更多
The development of distinct dendritic cell(DC)subsets,namely,plasmacytoid DCs(pDCs)and conventional DC subsets(cDC1s and cDC2s),is controlled by specific transcription factors.IRF8 is essential for the fate specificat...The development of distinct dendritic cell(DC)subsets,namely,plasmacytoid DCs(pDCs)and conventional DC subsets(cDC1s and cDC2s),is controlled by specific transcription factors.IRF8 is essential for the fate specification of cDC1s.However,how the expression of Irf8 is regulated is not fully understood.In this study,we identified TRIM33 as a critical regulator of DC differentiation and maintenance.TRIM33 deletion in Trim33fl/fl Cre-ERT2 mice significantly impaired DC differentiation from hematopoietic progenitors at different developmental stages.TRIM33 deficiency downregulated the expression of multiple genes associated with DC differentiation in these progenitors.TRIM33 promoted the transcription of Irf8 to facilitate the differentiation of cDC1s by maintaining adequate CDK9 and Ser2 phosphorylated RNA polymerase II(S2 Pol II)levels at Irf8 gene sites.Moreover,TRIM33 prevented the apoptosis of DCs and progenitors by directly suppressing the PU.1-mediated transcription of Bcl2l11,thereby maintaining DC homeostasis.Taken together,our findings identified TRIM33 as a novel and crucial regulator of DC differentiation and maintenance through the modulation of Irf8 and Bcl2l11 expression.The finding that TRIM33 functions as a critical regulator of both DC differentiation and survival provides potential benefits for devising DC-based immune interventions and therapies.展开更多
Microglial activation occurs in divergent neuropathological conditions.Such microglial event has the key involvement in the progression of CNS diseases.However,the transcriptional mechanism governing microglial activa...Microglial activation occurs in divergent neuropathological conditions.Such microglial event has the key involvement in the progression of CNS diseases.However,the transcriptional mechanism governing microglial activation remains poorly understood.Here,we investigate the microglial response to traumatic injuryinduced neurodegeneration by the 3D fluorescence imaging technique.We show that transcription factors IRF8 and PU.1 are both indispensible for microglial activation,as their specific post-developmental deletion in microglia abolishes the process.Mechanistically,we reveal that IRF8 and PU.1 directly target the gene transcription of each other in a positive feedback to sustain their highly enhaneed expression during microglial activation.Moreover,IRF8 and PU.1 dictate the microglial response by cooperatively acting through the composite IRF-ETS motifs that are specifically enriched on microglial activation-related genes.This action of cooperative transcription can be further verified bio chemically by the synergetic binding of IRF8 and PU.1 proteins to the composite-motif DNA.Our study has therefore elucidated the central transcriptional mechanism of microglial activation in response to neurodegenerative condition.展开更多
Recent studies have suggested that regulatory T （Treg） cells comprise a heterogeneous population that regulates various aspects of the immune response, and that Treg cells use the factors that are expressed in their...Recent studies have suggested that regulatory T （Treg） cells comprise a heterogeneous population that regulates various aspects of the immune response, and that Treg cells use the factors that are expressed in their target cells to regulate them. We searched for factors that regulate Thl response in Treg cells using a meta-analysis. In the process, we discovered that transcription factor interferon regulatory factor 8 （I RF8） was selectively expressed in Treg and Th I cells. IRF8-deficient Treg cells showed defective expression of CXCR3 and aberrant expression of the 114 and 1117genes. Upon treatment with alpha galactosyI-C18-ceramide （aGaI-C18-Cer）, IRF8-deficient mice showed defective Treg cell recruitment in the liver. Eliciting Thl immune response by anti-CD40 antibody injection in mice induced IRF8 expression in Treg cells. The expression of IRF8 was induced by Foxp3 in Treg cells, IRF8 had no effect on T-bet expression in Treg and vice versa. Thus, our results strongly suggest that IRF8 controls Thl immune response in Treg cells independent of T-bet.展开更多
Interferon regulatory factor 4 （IRF4） and IRF8 are critical regulators of immune system development and function. In B lymphocytes, IRF4 and IRF8 have been shown to control important events during their development ...Interferon regulatory factor 4 （IRF4） and IRF8 are critical regulators of immune system development and function. In B lymphocytes, IRF4 and IRF8 have been shown to control important events during their development and maturation including pre-B cell differentiation, induction of B cell tolerance pathways, marginal zone B cell development, germinal center reaction and plasma cell differentiation. Mechanistically, IRF4 and IRF8 are found to function redundantly to control certain stages of B cell development, but in other stages, they function nonredundantly to play distinct roles in B cell biology. In line with their essential roles in B cell development, deregulated expressions of IRF4 and IRF8 have been associated to the pathogenesis of several B cell malignancies and diseases. Recent studies have elucidated diverse transcriptional networks regulated by IRF4 and IRF8 at distinct B cell developmental stages and related malignancies. In this review we will discuss the recent advances for the roles of IRF4 and IRF8 during B cell development and associated diseases.展开更多
The morbidity and mortality of myeloproliferative neoplasms(MPNs)are primarily caused by arterial and venous complications,progression to myelofibrosis,and transformation to acute leukemia.However,identifying molecula...The morbidity and mortality of myeloproliferative neoplasms(MPNs)are primarily caused by arterial and venous complications,progression to myelofibrosis,and transformation to acute leukemia.However,identifying molecular-based biomarkers for risk stratification of patients with MPNs remains a challenge.We have previously shown that interferon regulatory factor-8(IRF8)and IRF4 serve as tumor suppressors in myeloid cells.In this study,we evaluated the expression of IRF4 and IRF8 and the JAK2V617F mutant allele burden in patients with MPNs.Patients with decreased IRF4 expression were correlated with a more developed MPN phenotype in myelofibrosis(MF)and secondary AML(sAML)transformed from MPNs versus essential thrombocythemia(ET).Negative correlations between the JAK2V617F allele burden and the expression of IRF8(P<0.05)and IRF4(P<0.001)and between white blood cell(WBC)count and IRF4 expression(P<0.05)were found in ET patients.IRF8 expression was negatively correlated with the JAK2V617F allele burden(P<0.05)in polycythemia vera patients.Complete response(CR),partial response(PR),and no response(NR)were observed in 67.5%,10%,and 22.5%of ET patients treated with hydroxyurea(HU),respectively,in 12 months.At 3 months,patients in the CR group showed high IRF4 and IRF8 expression compared with patients in the PR and NR groups.In the 12-month therapy period,low IRF4 and IRF8 expression were independently associated with the unfavorable response to HU and high WBC count.Our data indicate that the expression of IRF4 and IRF8 was associated with the MPN phenotype,which may serve as biomarkers for the response to HU in ET.展开更多
文摘目的:探讨鞘内注射小胶质细胞干扰素调节因子8(interferon regulatory factor 8,IRF8)反义寡核苷酸(oligodeoxynucleotide,ODN)对大鼠慢性坐骨神经缩窄损伤(chronic constriction injury of sciatic nerve,CCI)模型疼痛行为的影响。方法:雄性SD大鼠40只随机分为4组:Sham组、AS组、MM组、NS组,每组10只。除Sham组外,其他三组均鞘内置管并制备CCI模型,AS组、MM组、NS组依次于CCI后12 h鞘内注射IRF8反义/错义ODN、等体积生理盐水,1次/d,连续6 d。制模前测量各组大鼠的基础阈值,制模后1、3、5、7、10、12、14 d对大鼠进行疼痛行为测定。制模后7、14 d western blot检测IRF8、离子钙接合蛋白Iba1表达。结果:与Sham组比较,NS组、MM组大鼠神经损伤后右后爪机械痛阈和热痛阈均显著降低(P<0.05),脊髓IRF8、Iba1蛋白表达显著增强(P<0.05)。AS组于CCI后第10 d起右足机械痛阈和热痛阈下降,但仍高于MM组、NS组(P<0.05)。CCI后第7、14 d IRF8、Iba1蛋白表达,AS组较MM组、NS组显著减弱(P<0.05),但仍强于Sham组(P<0.05)。AS组第14 d IRF8、Iba1蛋白表达较第7 d增强(P<0.05)。结论:经鞘内注射IRF8反义寡核苷酸可抑制脊髓内IRF8表达和小胶质细胞活化而缓解CCI大鼠神经病理性疼痛。
基金supported by the National Natural Science Foundation of China under grants(No.81470230)the Natural Science Foundation of Guangxi Zhuang Autonomous Region under grants(No.2020GXNSFDA238003).
文摘Objective:To assess the effects of nebulized inhaled Mycobacterium vaccae on allergic airway inflammation,airway hyperresponsiveness,and Th1/Th2 cell imbalance in mice with ovalbumin(OVA)-induced asthma.Methods:Mice received OVA sensitization and challenge for establishment of the asthmatic model.For intervention,mice received Mycobacterium vaccae nebulization once every other day from the first day of sensitization to the day before challenge.After challenge,pulmonary histological analysis and airway responsiveness measurement were performed.In addition,Th1/Th2 cytokines and OVA-specific IgE levels in bronchoalveolar lavage fluid were measured by ELISA.Th1/Th2 subset ratios and the expression of interferon-regulatory factor 4(IRF4),IRF8 and Toll-like receptor 4(TLR4)in dendritic cells were evaluated by flow cytometry.Results:Severe inflammatory infiltration and airway hyperresponsiveness were observed in OVA-induced asthmatic mice.Asthmatic mice showed higher Th2 cytokine concentration and increased percentage of Th2 cells,along with lower Th1 cytokine concentration and reduced percentage of Th1 cells compared with the normal control.Moreover,an imbalance of IRF4^(+)and IRF8^(+)in dendritic cells was found in asthmatic mice.Nebulized inhaled Mycobacterium vaccae reduced airway hyperresponsiveness and inflammation in OVA-induced asthmatic mice.In addition,nebulized inhaled Mycobacterium vaccae enhanced TLR4 and IRF8 expression,and alleviated the imbalance of Th1/Th2 as well as IRF4^(+)and IRF8^(+)in dendritic cells.Conclusions:Nebulized inhaled Mycobacterium vaccae protects against asthma by alleviating the imbalance of Th1/Th2 and IRF4/IRF8 in OVA-induced asthmatic mice.
基金The Ministry of Science and Technology of China National Key Research Projects provided grants 2019YFA0508502 and 2022YFC2505001 to LWThe National Natural Science Foundation of China funded grant 31991174 to LW+4 种基金The National Natural Science Foundation of China provided Basic Research Center grant 82388101 to LWThe National Natural Science Foundation of China provided grant 81801641 to JLThe National Natural Science Foundation of China provided grant 31800769 to ZHThe Ministry of Science and Technology of China National Key Research Projects provided grants 2022YFC2505002 to TWFunding from the Tsinghua-Peking Center for Life Sciences to LW is acknowledged.
文摘The development of distinct dendritic cell(DC)subsets,namely,plasmacytoid DCs(pDCs)and conventional DC subsets(cDC1s and cDC2s),is controlled by specific transcription factors.IRF8 is essential for the fate specification of cDC1s.However,how the expression of Irf8 is regulated is not fully understood.In this study,we identified TRIM33 as a critical regulator of DC differentiation and maintenance.TRIM33 deletion in Trim33fl/fl Cre-ERT2 mice significantly impaired DC differentiation from hematopoietic progenitors at different developmental stages.TRIM33 deficiency downregulated the expression of multiple genes associated with DC differentiation in these progenitors.TRIM33 promoted the transcription of Irf8 to facilitate the differentiation of cDC1s by maintaining adequate CDK9 and Ser2 phosphorylated RNA polymerase II(S2 Pol II)levels at Irf8 gene sites.Moreover,TRIM33 prevented the apoptosis of DCs and progenitors by directly suppressing the PU.1-mediated transcription of Bcl2l11,thereby maintaining DC homeostasis.Taken together,our findings identified TRIM33 as a novel and crucial regulator of DC differentiation and maintenance through the modulation of Irf8 and Bcl2l11 expression.The finding that TRIM33 functions as a critical regulator of both DC differentiation and survival provides potential benefits for devising DC-based immune interventions and therapies.
基金State Key Laboratory of Membrane Biology,IDG/McGovern Institute for Brain Research,Center for Life Sciences and School of Life Sciences at Peking University,and National Natural Science Foundation of China to J.Yang(Grant Nos.31522024 and 31771111).
文摘Microglial activation occurs in divergent neuropathological conditions.Such microglial event has the key involvement in the progression of CNS diseases.However,the transcriptional mechanism governing microglial activation remains poorly understood.Here,we investigate the microglial response to traumatic injuryinduced neurodegeneration by the 3D fluorescence imaging technique.We show that transcription factors IRF8 and PU.1 are both indispensible for microglial activation,as their specific post-developmental deletion in microglia abolishes the process.Mechanistically,we reveal that IRF8 and PU.1 directly target the gene transcription of each other in a positive feedback to sustain their highly enhaneed expression during microglial activation.Moreover,IRF8 and PU.1 dictate the microglial response by cooperatively acting through the composite IRF-ETS motifs that are specifically enriched on microglial activation-related genes.This action of cooperative transcription can be further verified bio chemically by the synergetic binding of IRF8 and PU.1 proteins to the composite-motif DNA.Our study has therefore elucidated the central transcriptional mechanism of microglial activation in response to neurodegenerative condition.
文摘Recent studies have suggested that regulatory T （Treg） cells comprise a heterogeneous population that regulates various aspects of the immune response, and that Treg cells use the factors that are expressed in their target cells to regulate them. We searched for factors that regulate Thl response in Treg cells using a meta-analysis. In the process, we discovered that transcription factor interferon regulatory factor 8 （I RF8） was selectively expressed in Treg and Th I cells. IRF8-deficient Treg cells showed defective expression of CXCR3 and aberrant expression of the 114 and 1117genes. Upon treatment with alpha galactosyI-C18-ceramide （aGaI-C18-Cer）, IRF8-deficient mice showed defective Treg cell recruitment in the liver. Eliciting Thl immune response by anti-CD40 antibody injection in mice induced IRF8 expression in Treg cells. The expression of IRF8 was induced by Foxp3 in Treg cells, IRF8 had no effect on T-bet expression in Treg and vice versa. Thus, our results strongly suggest that IRF8 controls Thl immune response in Treg cells independent of T-bet.
文摘Interferon regulatory factor 4 （IRF4） and IRF8 are critical regulators of immune system development and function. In B lymphocytes, IRF4 and IRF8 have been shown to control important events during their development and maturation including pre-B cell differentiation, induction of B cell tolerance pathways, marginal zone B cell development, germinal center reaction and plasma cell differentiation. Mechanistically, IRF4 and IRF8 are found to function redundantly to control certain stages of B cell development, but in other stages, they function nonredundantly to play distinct roles in B cell biology. In line with their essential roles in B cell development, deregulated expressions of IRF4 and IRF8 have been associated to the pathogenesis of several B cell malignancies and diseases. Recent studies have elucidated diverse transcriptional networks regulated by IRF4 and IRF8 at distinct B cell developmental stages and related malignancies. In this review we will discuss the recent advances for the roles of IRF4 and IRF8 during B cell development and associated diseases.
基金supported by the National Key Research and Development Program(No.2016YFC0902800 to Ruibao Ren)the Key Project of National Natural Science Foundation of China(No.81530006 to Ruibao Ren)+1 种基金Shanghai Collaborative Innovation Program on Regenerative Medicine and Stem Cell Research(No.2019CXJQ01 to Ruibao Ren)National Natural Science Foundation of China(No.81870112 to Ruibao Ren).
文摘The morbidity and mortality of myeloproliferative neoplasms(MPNs)are primarily caused by arterial and venous complications,progression to myelofibrosis,and transformation to acute leukemia.However,identifying molecular-based biomarkers for risk stratification of patients with MPNs remains a challenge.We have previously shown that interferon regulatory factor-8(IRF8)and IRF4 serve as tumor suppressors in myeloid cells.In this study,we evaluated the expression of IRF4 and IRF8 and the JAK2V617F mutant allele burden in patients with MPNs.Patients with decreased IRF4 expression were correlated with a more developed MPN phenotype in myelofibrosis(MF)and secondary AML(sAML)transformed from MPNs versus essential thrombocythemia(ET).Negative correlations between the JAK2V617F allele burden and the expression of IRF8(P<0.05)and IRF4(P<0.001)and between white blood cell(WBC)count and IRF4 expression(P<0.05)were found in ET patients.IRF8 expression was negatively correlated with the JAK2V617F allele burden(P<0.05)in polycythemia vera patients.Complete response(CR),partial response(PR),and no response(NR)were observed in 67.5%,10%,and 22.5%of ET patients treated with hydroxyurea(HU),respectively,in 12 months.At 3 months,patients in the CR group showed high IRF4 and IRF8 expression compared with patients in the PR and NR groups.In the 12-month therapy period,low IRF4 and IRF8 expression were independently associated with the unfavorable response to HU and high WBC count.Our data indicate that the expression of IRF4 and IRF8 was associated with the MPN phenotype,which may serve as biomarkers for the response to HU in ET.
