High mobility group box 1(HMGB1)is an evolutionarily conserved non-histone chromatin-binding protein.During infection or injury,activated immune cells and damaged cells release HMGB1 into the extracellular space,where...High mobility group box 1(HMGB1)is an evolutionarily conserved non-histone chromatin-binding protein.During infection or injury,activated immune cells and damaged cells release HMGB1 into the extracellular space,where HMGB1 functions as a proinflammatory mediator and contributes importantly to the pathogenesis of inflammatory diseases.Recent studies reveal that infl ammasomes,intracellular protein complexes,critically regulate HMGB1 release from activated immune cells in response to a variety of exogenous and endogenous danger signals.Double stranded RNA dependent kinase(PKR),an intracellular danger-sensing molecule,physically interacts with inflammasome components and is important for infl ammasome activation and HMGB1 release.Together,these studies not only unravel novel mechanisms of HMGB1 release during infl ammation,but also provide potential therapeutic targets to treat HMGB1-related infl ammatory diseases.展开更多
The cysteine protease caspase-1(Casp-1)contributes to innate immunity through the assembly of NLRP3,NLRC4,AIM2,and NLRP6 inflammasomes.Here we ask whether caspase-1 activation plays a regulatory role in house dust mit...The cysteine protease caspase-1(Casp-1)contributes to innate immunity through the assembly of NLRP3,NLRC4,AIM2,and NLRP6 inflammasomes.Here we ask whether caspase-1 activation plays a regulatory role in house dust mite(HDM)-induced experimental allergic airway inflammation.We report enhanced airway inflammation in caspase-1-deficient mice exposed toHDMwith a marked eosinophil recruitment,increased expression of IL-4,IL-5,IL-13,aswell as full-length and bioactive IL-33.Furthermore,mice deficient for NLRP3 failed to control eosinophil influx in the airways and displayed augmented Th2 cytokine and chemokine levels,suggesting that the NLPR3 inflammasome complex controls HDM-induced inflammation.IL-33 neutralization by administration of soluble ST2 receptor inhibited the enhanced allergic inflammation,while administration of recombinant IL-33 during challenge phase enhanced allergic inflammation in caspase-1-deficient mice.Therefore,we show that caspase-1,NLRP3,and ASC,but not NLRC4,contribute to the upregulation of allergic lung inflammation.Moreover,we cannot exclude an effect of caspase-11,because caspase-1-deficient mice are deficient for both caspases.Mechanistically,absence of caspase-1 is associated with increased expression of IL-33,uric acid,and spleen tyrosine kinase(Syk)production.This study highlights acritical role of caspase-1 activation andNLPR3/ASCinflammasomecomplex in the down-modulation of IL-33 in vivo and in vitro,thereby regulating Th2 response in HDM-induced allergic lung inflammation.展开更多
Infl ammasomes are multiprotein complexes that serve as a platform for caspase-1 activation and interleukin-1β(IL-1β)maturation as well as pyroptosis.Though a number of infl ammasomes have been described,the NLRP3 i...Infl ammasomes are multiprotein complexes that serve as a platform for caspase-1 activation and interleukin-1β(IL-1β)maturation as well as pyroptosis.Though a number of infl ammasomes have been described,the NLRP3 inflammasome is the most extensively studied.NLRP3 inflammasome is triggered by a variety of stimuli,including infection,tissue damage and metabolic dysregulation,and then activated through an integrated cellular signal.Many regulatory mechanisms have been identifi ed to attenuate NLRP3 infl ammasome signaling at multiple steps.Here,we review the developments in the negative regulation of NLRP3 inflammasome that protect host from inflammatory damage.展开更多
文摘High mobility group box 1(HMGB1)is an evolutionarily conserved non-histone chromatin-binding protein.During infection or injury,activated immune cells and damaged cells release HMGB1 into the extracellular space,where HMGB1 functions as a proinflammatory mediator and contributes importantly to the pathogenesis of inflammatory diseases.Recent studies reveal that infl ammasomes,intracellular protein complexes,critically regulate HMGB1 release from activated immune cells in response to a variety of exogenous and endogenous danger signals.Double stranded RNA dependent kinase(PKR),an intracellular danger-sensing molecule,physically interacts with inflammasome components and is important for infl ammasome activation and HMGB1 release.Together,these studies not only unravel novel mechanisms of HMGB1 release during infl ammation,but also provide potential therapeutic targets to treat HMGB1-related infl ammatory diseases.
基金support by University of Orleans,la Region Centre(HabitAsthmeN8201200073535)and Conseil General45 to F.M.as PhD fellowship.
文摘The cysteine protease caspase-1(Casp-1)contributes to innate immunity through the assembly of NLRP3,NLRC4,AIM2,and NLRP6 inflammasomes.Here we ask whether caspase-1 activation plays a regulatory role in house dust mite(HDM)-induced experimental allergic airway inflammation.We report enhanced airway inflammation in caspase-1-deficient mice exposed toHDMwith a marked eosinophil recruitment,increased expression of IL-4,IL-5,IL-13,aswell as full-length and bioactive IL-33.Furthermore,mice deficient for NLRP3 failed to control eosinophil influx in the airways and displayed augmented Th2 cytokine and chemokine levels,suggesting that the NLPR3 inflammasome complex controls HDM-induced inflammation.IL-33 neutralization by administration of soluble ST2 receptor inhibited the enhanced allergic inflammation,while administration of recombinant IL-33 during challenge phase enhanced allergic inflammation in caspase-1-deficient mice.Therefore,we show that caspase-1,NLRP3,and ASC,but not NLRC4,contribute to the upregulation of allergic lung inflammation.Moreover,we cannot exclude an effect of caspase-11,because caspase-1-deficient mice are deficient for both caspases.Mechanistically,absence of caspase-1 is associated with increased expression of IL-33,uric acid,and spleen tyrosine kinase(Syk)production.This study highlights acritical role of caspase-1 activation andNLPR3/ASCinflammasomecomplex in the down-modulation of IL-33 in vivo and in vitro,thereby regulating Th2 response in HDM-induced allergic lung inflammation.
文摘Infl ammasomes are multiprotein complexes that serve as a platform for caspase-1 activation and interleukin-1β(IL-1β)maturation as well as pyroptosis.Though a number of infl ammasomes have been described,the NLRP3 inflammasome is the most extensively studied.NLRP3 inflammasome is triggered by a variety of stimuli,including infection,tissue damage and metabolic dysregulation,and then activated through an integrated cellular signal.Many regulatory mechanisms have been identifi ed to attenuate NLRP3 infl ammasome signaling at multiple steps.Here,we review the developments in the negative regulation of NLRP3 inflammasome that protect host from inflammatory damage.
