Cytokines are indispensable signals of the mucosaassociated immune system for maintaining normal gut homeostasis.An imbalance of their profile in favour of inflammation initiation may lead to disease states,such as th...Cytokines are indispensable signals of the mucosaassociated immune system for maintaining normal gut homeostasis.An imbalance of their profile in favour of inflammation initiation may lead to disease states,such as that is observed in inflammatory bowel diseases(IBD).Although Crohn's disease(CD) is often described as a prototype of T-helper 1-type diseases,and ulcerative colitis(UC) is traditionally viewed as a T-helper 2-mediated condition,the classic paradigm,which categorises cytokines into pro-and anti-inflammatory groups,has recently been changed.The inflammation regulatory pathways may not be mutually exclusive as individual cytokines can have diverse and even opposing functions in various clinical and immunological settings.None the less there are many common immunological responses in IBD that are mediated by cytokines.Although they regulate and influence the development,course and recurrence of the inflammatory process,the concrete pathogenic role of these small signaling molecules is sometimes not unambiguous in the subtypes of the disease.Our aim is to review the current information about pro-and anti-inflammatory effects of traditionally studied and recently discovered cytokines in the pathogenesis of UC and CD.The better understanding of their production and functional activity may lead to the development of new therapeutic modalities.展开更多
Innate immunity offers the first line of defense against infections and other types of danger such as tumorigenesis. Its discovery provides tremendous therapeutic opportunities for numerous human diseases. Delving int...Innate immunity offers the first line of defense against infections and other types of danger such as tumorigenesis. Its discovery provides tremendous therapeutic opportunities for numerous human diseases. Delving into the structural basis of signal transduction by innate immune receptors, our lab has recently helped to establish the new paradigm in which innate immune receptors transduce ligand-binding signals through formation of higher-order assemblies containing intracellular adapters, signaling enzymes and their substrates. These large signalosome assemblies may be visible under light microscopy as punctate structures in the μm scale, connecting to the underlying molecular structures in the nm scale. They drive proximity-induced enzyme activation, and provide a mechanism for signaling amplification by nucleated polymerization. These supramolecular signaling complexes also open new questions on their cellular organization and mode of regulation, pose challenges to our methodology, and afford valuable implications in drug discovery against these medically important pathways.展开更多
For antiviral signaling mediated by retinoic acid-inducible gene I (RiG-I)-like receptors (RLRs), the recruitment of cytosoUc RLRs and downstream molecules (such as TBK1 and IKKε) to mitochondriaL platform is a...For antiviral signaling mediated by retinoic acid-inducible gene I (RiG-I)-like receptors (RLRs), the recruitment of cytosoUc RLRs and downstream molecules (such as TBK1 and IKKε) to mitochondriaL platform is a central event that facilitates the establishment of host antiviral state. Here, we present an example of viral targeting for immune evasion through spatial isolation of TBK1/IKKε from mitochond riai antiviral platform, which was employed by severe fever with thrombocytopenia syndrome virus (SFTSV), a deadly bunyavirus emerging recently. We showed that SFTSV nonstructural protein NSs functions as the interferon (IFN) antagonist, mainly via suppressing TBK1/IKKε-IRF3 signaling. NSs mediates the formation of cytoplasmic inclusion bodies (IBs), and the blockage of IB formation impairs IFN-inhibiting activity of NSs. We next demonstrate that I Bs are utilized to compartmentalize TBK1/I KKε. The compartmentalization results in spatial isolation of the kinases from mitochondria, and deprived TBK1/IKKε may participate in antiviral complex assembly, leadingto the blockage of lFN ind uction. This study proposes a new role of viral I Bs as virus-built'jail' for imprisoning cellular factors and presents a novel and likely common mechanism of viral immune evasion through spatial isolation of critical signaling molecules from the mitochondrial antiviral platform.展开更多
文摘Cytokines are indispensable signals of the mucosaassociated immune system for maintaining normal gut homeostasis.An imbalance of their profile in favour of inflammation initiation may lead to disease states,such as that is observed in inflammatory bowel diseases(IBD).Although Crohn's disease(CD) is often described as a prototype of T-helper 1-type diseases,and ulcerative colitis(UC) is traditionally viewed as a T-helper 2-mediated condition,the classic paradigm,which categorises cytokines into pro-and anti-inflammatory groups,has recently been changed.The inflammation regulatory pathways may not be mutually exclusive as individual cytokines can have diverse and even opposing functions in various clinical and immunological settings.None the less there are many common immunological responses in IBD that are mediated by cytokines.Although they regulate and influence the development,course and recurrence of the inflammatory process,the concrete pathogenic role of these small signaling molecules is sometimes not unambiguous in the subtypes of the disease.Our aim is to review the current information about pro-and anti-inflammatory effects of traditionally studied and recently discovered cytokines in the pathogenesis of UC and CD.The better understanding of their production and functional activity may lead to the development of new therapeutic modalities.
文摘Innate immunity offers the first line of defense against infections and other types of danger such as tumorigenesis. Its discovery provides tremendous therapeutic opportunities for numerous human diseases. Delving into the structural basis of signal transduction by innate immune receptors, our lab has recently helped to establish the new paradigm in which innate immune receptors transduce ligand-binding signals through formation of higher-order assemblies containing intracellular adapters, signaling enzymes and their substrates. These large signalosome assemblies may be visible under light microscopy as punctate structures in the μm scale, connecting to the underlying molecular structures in the nm scale. They drive proximity-induced enzyme activation, and provide a mechanism for signaling amplification by nucleated polymerization. These supramolecular signaling complexes also open new questions on their cellular organization and mode of regulation, pose challenges to our methodology, and afford valuable implications in drug discovery against these medically important pathways.
基金Acknowtedgements We thank Dr Hong-Bing Shu (Wuhan University, China) for supplying reporter and expression plasmids. This work was supported by the National Science Foundation of China (grant numbers 31125003 and 31321001), the Science and Technology Basic Work Program (grant number 2013FY113500), and the National Basic Research Program (973 Program) of China (grant numbers 2010CB530100 and 2013CB911101).
文摘For antiviral signaling mediated by retinoic acid-inducible gene I (RiG-I)-like receptors (RLRs), the recruitment of cytosoUc RLRs and downstream molecules (such as TBK1 and IKKε) to mitochondriaL platform is a central event that facilitates the establishment of host antiviral state. Here, we present an example of viral targeting for immune evasion through spatial isolation of TBK1/IKKε from mitochond riai antiviral platform, which was employed by severe fever with thrombocytopenia syndrome virus (SFTSV), a deadly bunyavirus emerging recently. We showed that SFTSV nonstructural protein NSs functions as the interferon (IFN) antagonist, mainly via suppressing TBK1/IKKε-IRF3 signaling. NSs mediates the formation of cytoplasmic inclusion bodies (IBs), and the blockage of IB formation impairs IFN-inhibiting activity of NSs. We next demonstrate that I Bs are utilized to compartmentalize TBK1/I KKε. The compartmentalization results in spatial isolation of the kinases from mitochondria, and deprived TBK1/IKKε may participate in antiviral complex assembly, leadingto the blockage of lFN ind uction. This study proposes a new role of viral I Bs as virus-built'jail' for imprisoning cellular factors and presents a novel and likely common mechanism of viral immune evasion through spatial isolation of critical signaling molecules from the mitochondrial antiviral platform.