04416nam 2200445 450 991013680080332120230808192419.0(CKB)3710000000631114(oapen)https://directory.doabooks.org/handle/20.500.12854/43454(EXLCZ)99371000000063111420160411h20162016 fu 0engurmn#---|||||txtrdacontentcrdamediacrrdacarrierThe coevolution of IDO1 and AHR in the emergence of regulatory T cells in mammals[electronic resource] /edited by Ursula Grohmann and Paolo PuccettiFrontiers Media SA2016Lausanne, Switzerland :Frontiers Media SA,2016.©20161 online resource (89 pages) illustrations, charts; digital, PDF file(s)Frontiers research topicsPublished in Frontiers in Immunology.2-88919-729-8 Indoleamine 2,3-dioxygenase (IDO1) is an ancestral enzyme that, initially confined to the regulation of tryptophan availability in local tissue microenvironments, is now considered to play a wider role that extends to homeostasis and plasticity of the immune system. Thus IDO biology has implications for many aspects of immunopathology, including viral infections, neoplasia, autoimmunity, and chronic inflammation. Its immunoregulatory effects are mainly mediated by dendritic cells (DCs) and involve not only tryptophan deprivation but also production of kynurenines that act on IDO− DCs, thus rendering an otherwise stimulatory DC capable of regulatory effects, as well as on T cells. The aryl hydrocarbon receptor (AhR) is a ligand-operated transcription factor originally recognized as the effector mediating the pathologic effects of dioxins and other pollutants. However, it is now well established that AhR activation by endogenous ligands can produce immunoregulatory effects. The IDO1 mechanism appears to have been selected through phylogenesis primarily to prevent overreacting responses to TLR-recognized pathogen-associated molecular patterns, and only later did it become involved in the response to T cell receptor-recognized antigens. As a result, in mammals, IDO1 has become pivotal in fetomaternal tolerance, at a time when regulatory T cells emerged to meet the same need, namely protecting the fetus. IDO1 and regulatory T (Treg) cells may have then coevolved to broaden their function well beyond their initial task of protecting the fetus, such that, in acquired immunity, IDO1 (with its dual enzymic and signaling function) has turned into an important component of the peripheral generation and effector function of regulatory T cells. AhR, in turn, which has a role in regulatory T-cell generation, is presumed to have evolved from invertebrates, where it served a ligand-independent role in normal development processes. Evolution of the receptor in vertebrates resulted in the ability to bind structurally different ligands, including xenobiotics and microbiota-derived catabolites. Considering the inability of invertebrate AhR homologs to bind dioxins, the adaptive role of the AhR to act as a regulator of xenobiotic-metabolizing enzymes may have been a vertebrate innovation, to later acquire an additional immune regulatory role by coevolutive pressure in mammals by IDO1 and regulatory T cells. Thus an entirely new paradigm in immunology, and more specifically in immune tolerance, is the coevolution of three systems, namely, the IDO1 mechanism, AhR-driven gene transcription, and T-cell regulatory activity, that originating from the initial need of protecting the fetus in mammals, have later turned into a pivotal mechanism of peripheral tolerance in autoimmunity, transplantation, and neoplasia.ImmunologyAryl hydrocarbon receptor (AhR)indoleamine dioxygenase 1 and 2 (IDO1 and IDO2)tryptophan dioxygenase (TDO2)tryptophan metabolismImmune RegulationImmunology.Ursula Grohmannauth1376090Grohmann. UrsulaPuccetti PaoloUkMaJRUBOOK9910136800803321The coevolution of IDO1 and AHR in the emergence of regulatory T cells in mammals3411381UNINA04137nam 22007455 450 991048339160332120200919110255.03-319-04660-810.1007/978-3-319-04660-0(CKB)3710000000093991(EBL)1697926(OCoLC)880449610(SSID)ssj0001187516(PQKBManifestationID)11662845(PQKBTitleCode)TC0001187516(PQKBWorkID)11243997(PQKB)10962525(MiAaPQ)EBC1697926(DE-He213)978-3-319-04660-0(PPN)177822090(EXLCZ)99371000000009399120140311d2014 u| 0engur|n|---|||||txtccrScientific Objectivity and Its Contexts /by Evandro Agazzi1st ed. 2014.Cham :Springer International Publishing :Imprint: Springer,2014.1 online resource (492 p.)Description based upon print version of record.3-319-04659-4 Includes bibliographical references and index.Historical and Philosophical Background -- The Characterisation of Objectivity -- First Corollaries in the Philosophy of Science -- The Ontological Commitment of Science -- Scientific Realism -- The Contexts of Objectivity -- Corollaries in the Philosophy of Science -- Scientific Truth Revisited -- The Context of Making Science -- Science and Metaphysics -- Appendix -- References -- Indexes.The first part of this book is of an epistemological nature and develops an original theory of scientific objectivity, understood in a weak sense (as intersubjective agreement among the specialists) and a strong sense (as having precise concrete referents). In both cases it relies upon the adoption of operational criteria designed within the particular perspective under which any single science considers reality. The “object” so attained has a proper ontological status, dependent on the specific character of the criteria of reference (regional ontologies). This justifies a form of scientific realism. Such perspectives are also the result of a complex cultural-historical situation. The awareness of such a “historical determinacy” of science justifies including in the philosophy of science the problems of ethics of science, relations of science with metaphysics, and social dimensions of science that overstep the traditional restriction of the philosophy of science to an epistemology of science. It is to this “context” that the second part of the book is devoted.Philosophy and sciencePhysicsLogic, Symbolic and mathematicalEthicsPhilosophy of naturePhilosophy of Sciencehttps://scigraph.springernature.com/ontologies/product-market-codes/E34000History and Philosophical Foundations of Physicshttps://scigraph.springernature.com/ontologies/product-market-codes/P29000Mathematical Logic and Foundationshttps://scigraph.springernature.com/ontologies/product-market-codes/M24005Ethicshttps://scigraph.springernature.com/ontologies/product-market-codes/E14000Philosophy of Naturehttps://scigraph.springernature.com/ontologies/product-market-codes/E34040Philosophy and science.Physics.Logic, Symbolic and mathematical.Ethics.Philosophy of nature.Philosophy of Science.History and Philosophical Foundations of Physics.Mathematical Logic and Foundations.Ethics.Philosophy of Nature.10113170501Agazzi Evandroauthttp://id.loc.gov/vocabulary/relators/aut9620BOOK9910483391603321Scientific Objectivity and Its Contexts2597587UNINA