Biologie Digitale de l’ARN

@article{flacher_murine_2014,

title = {Murine Langerin+ dermal dendritic cells prime CD8+ Ŧ cells while Langerhans cells induce cross-tolerance},

author = {Vincent Flacher and Christoph H Tripp and David G Mairhofer and Ralph M Steinman and Patrizia Stoitzner and Juliana Idoyaga and Nikolaus Romani},

doi = {10.15252/emmm.201303283},

issn = {1757-4684},

year  = {2014},

date = {2014-09-01},

journal = {EMBO molecular medicine},

volume = {6},

number = {9},

pages = {1191--1204},

abstract = {Skin dendritic cells (DCs) control the immunogenicity of cutaneously administered vaccines. Antigens targeted to DCs via the C-type lectin Langerin/CD207 are cross-presented to CD8(+) T cells in vivo. We investigated the relative roles of Langerhans cells (LCs) and Langerin(+) dermal DCs (dDCs) in different vaccination settings. Poly(I:C) and anti-CD40 agonist antibody promoted cytotoxic responses upon intradermal immunization with ovalbumin (OVA)-coupled anti-Langerin antibodies (Langerin/OVA). This correlated with CD70 upregulation in Langerin(+) dDCs, but not LCs. In chimeric mice where Langerin targeting was restricted to dDCs, CD8(+) T-cell memory was enhanced. Conversely, providing Langerin/OVA exclusively to LCs failed to prime cytotoxicity, despite initial antigen cross-presentation to CD8(+) T cells. Langerin/OVA combined with imiquimod could not prime CD8(+) T cells and resulted in poor cytotoxicity in subsequent responses. This tolerance induction required targeting and maturation of LCs. Altogether, Langerin(+) dDCs prime long-lasting cytotoxic responses, while cross-presentation by LCs negatively influences CD8(+) T-cell priming. Moreover, this highlights that DCs exposed to TLR agonists can still induce tolerance and supports the existence of qualitatively different DC maturation programs.},

keywords = {agonists, Animals, Antibodies, antibody, Antigen, Antigen Presentation, Antigens, C-Type, C-type lectin, cancer, CD70, CD8-Positive T-Lymphocytes, CD8+ T cells, CD8+ T‐cell responses, Cellular, CROSS-PRESENTATION, Cross-Priming, Cytotoxicity, Dendritic Cells, DERMAL DENDRITIC CELLS, DERMATOLOGY, disease, imiquimod, Immunization, IMMUNOGENICITY, Immunologic Memory, Immunological, Immunology, In vivo, Inbred C57BL, INDUCTION, Intradermal, Langerhans Cells, LECTIN, Lectins, Mannose-Binding Lectins, Maturation, Mice, Models, murine, OVALBUMIN, physiology, priming, RESPONSES, Skin, Surface, T CELLS, T-CELLS, Team-Mueller, tolerance, Vaccination, vaccine, Vaccines},

pubstate = {published},

tppubtype = {article}

}

@article{romani_targeting_2012,

title = {Targeting skin dendritic cells to improve intradermal vaccination},

author = {N Romani and V Flacher and C H Tripp and F Sparber and S Ebner and P Stoitzner},

doi = {10.1007/82_2010_118},

issn = {0070-217X},

year  = {2012},

date = {2012-01-01},

journal = {Current Topics in Microbiology and Immunology},

volume = {351},

pages = {113--138},

abstract = {Vaccinations in medicine are typically administered into the muscle beneath the skin or into the subcutaneous fat. As a consequence, the vaccine is immunologically processed by antigen-presenting cells of the skin or the muscle. Recent evidence suggests that the clinically seldom used intradermal route is effective and possibly even superior to the conventional subcutaneous or intramuscular route. Several types of professional antigen-presenting cells inhabit the healthy skin. Epidermal Langerhans cells (CD207/langerin(+)), dermal langerin(neg), and dermal langerin(+) dendritic cells (DC) have been described, the latter subset so far only in mouse skin. In human skin langerin(neg) dermal DC can be further classified based on their reciprocal expression of CD1a and CD14. The relative contributions of these subsets to the generation of immunity or tolerance are still unclear. Yet, specializations of these different populations have become apparent. Langerhans cells in human skin appear to be specialized for induction of cytotoxic T lymphocytes; human CD14(+) dermal DC can promote antibody production by B cells. It is currently attempted to rationally devise and improve vaccines by harnessing such specific properties of skin DC. This could be achieved by specifically targeting functionally diverse skin DC subsets. We discuss here advances in our knowledge on the immunological properties of skin DC and strategies to significantly improve the outcome of vaccinations by applying this knowledge.},

keywords = {Adaptive Immunity, administration & dosage, Analysis, Animals, Antibodies, antibody, Antigen, ANTIGEN PRESENTING CELLS, Antigen-Presenting Cells, Antigens, B CELLS, B-Lymphocytes, Bacterial Infections, Biosynthesis, C-Type, CD, CD14, CD1a, Cell Lineage, cytokine, Cytokines, cytology, Cytotoxic, Dendritic Cells, DERMATOLOGY, DERMIS, Drug Delivery Systems, Expression, Human, Humans, Immunity, Immunology, INDUCTION, Injections, Innate, Intradermal, Langerhans Cells, LECTIN, Lectins, Lymphocyte Activation, Lymphocytes, Mannose-Binding Lectins, methods, Mice, mouse, Muscle, prevention & control, PRODUCTION, Protein, review, Skin, SUBSETS, T-Lymphocytes, Team-Mueller, tolerance, Vaccination, vaccine, Vaccines, Virus Diseases},

pubstate = {published},

tppubtype = {article}

}

@article{romani_targeting_2010,

title = {Targeting of antigens to skin dendritic cells: possibilities to enhance vaccine efficacy},

author = {Nikolaus Romani and Martin Thurnher and Juliana Idoyaga and Ralph M Steinman and Vincent Flacher},

doi = {10.1038/icb.2010.39},

issn = {1440-1711},

year  = {2010},

date = {2010-01-01},

journal = {Immunology and Cell Biology},

volume = {88},

number = {4},

pages = {424--430},

abstract = {Vaccinations in medicine are commonly administered through the skin. Therefore, the vaccine is immunologically processed by antigen-presenting cells of the skin. There is recent evidence that the clinically less often used intradermal route is effective; in cases even superior to the conventional subcutaneous or intramuscular route. Professional antigen-presenting cells of the skin comprise epidermal Langerhans cells (CD207/langerin(+)), dermal langerin(-) and dermal langerin(+) dendritic cells (DCs). In human skin, langerin(-) dermal DCs can be further subdivided on the basis of their reciprocal CD1a and CD14 expression. The relative contributions of these subsets to the generation of immunity or tolerance are still unclear. Langerhans cells in human skin seem to be specialized for induction of cytotoxic T lymphocytes. Likewise, mouse Langerhans cells are capable of cross-presentation and of protecting against experimental tumours. It is desirable to harness these properties for immunotherapy. A promising strategy to dramatically improve the outcome of vaccinations is 'antigen targeting'. Thereby, the vaccine is delivered directly and selectively to defined types of skin DCs. Targeting is achieved by means of coupling antigen to antibodies that recognize cell surface receptors on DCs. This approach is being widely explored. Little is known, however, about the events that take place in the skin and the DCs subsets involved therein. This topic will be discussed in this article.},

keywords = {Animals, Antibodies, antibody, Antigen, ANTIGEN PRESENTING CELLS, Antigen-Presenting Cells, Antigens, C-Type, CD, CD14, CD1a, CROSS-PRESENTATION, Dendritic Cells, DERMATOLOGY, Expression, Human, Humans, Immunity, Immunotherapy, INDUCTION, Intradermal, Langerhans Cells, Lectins, Lymphocytes, Mannose-Binding Lectins, mouse, Receptor, Skin, SUBSETS, T-Lymphocytes, Team-Mueller, tolerance, Vaccination, vaccine, Vaccines},

pubstate = {published},

tppubtype = {article}

}

@article{tripp_lymph_2008,

title = {The lymph vessel network in mouse skin visualised with antibodies against the hyaluronan receptor LYVE-1},

author = {Christoph H Tripp and Bernhard Haid and Vincent Flacher and Michael Sixt and Hannes Peter and Julia Farkas and Robert Gschwentner and Lydia Sorokin and Nikolaus Romani and Patrizia Stoitzner},

doi = {10.1016/j.imbio.2008.07.025},

issn = {0171-2985},

year  = {2008},

date = {2008-01-01},

journal = {Immunobiology},

volume = {213},

number = {9-10},

pages = {715--728},

abstract = {Langerhans cells and dermal dendritic cells migrate to the draining lymph nodes through dermal lymphatic vessels. They do so in the steady-state and under inflammatory conditions. Peripheral T cell tolerance or T cell priming, respectively, are the consequences of migration. The nature of dendritic cell-containing vessels was mostly defined by electron microscopy or by their lack of blood endothelial markers. Selective markers for murine lymph endothelium were hitherto rare or not available. Here, we utilised recently developed antibodies against the murine hyaluronan receptor, LYVE-1, to study the lymph vessel network in mouse skin in more detail. In hairless skin from the ears, lymph vessels were spread out in a horizontal plane. They formed anastomoses, and they possessed frequent blind endings that were occasionally open. Lymph vessels were wider than blood vessels, which were identified by their strong CD31 expression. In body wall skin LYVE-1 reactive vessels did not extend laterally but they dived straight down into the deeper dermis. There, they are connected to each other and formed a network similar to ear skin. The number and width of lymph vessels did not grossly change upon inflammatory stimuli such as skin explant culture or tape stripping. There were also no marked changes in caliber in response to the TLR 7/8 ligand Imiquimod. Double-labelling experiments of cultured skin showed that most of the strongly cell surface MHC II-expressing (i.e. activated) dendritic cells were confined to the lymph vessels. Langerin/CD207(+) cells within this population appeared later than dermal dendritic cells, i.e. langerin-negative cells. Comparable results were obtained after stimulating the skin in vivo with the TLR 7/8 ligand Imiquimod or by tape stripping. In untreated skin (i.e. steady state) a few MHC II(+) and Langerin/CD207(+) cells, presumably migrating skin dendritic cells including epidermal Langerhans cells, were consistently observed within the lymph vessels. The novel antibody reagents may serve as important tools to further study the dendritic cell traffic in the skin under physiological conditions as well as in conditions of adoptive dendritic cell transfer in immunotherapy.},

keywords = {anatomy & histology, Animals, Antibodies, antibody, BLOOD, Blood Vessels, CD31, Cell Movement, Culture, cytology, Dendritic Cells, DERMAL DENDRITIC CELLS, DERMATOLOGY, DERMIS, EAR, electron microscopy, ENDOTHELIUM, Expression, GLYCOPROTEIN, Glycoproteins, hyaluronan, imiquimod, Immunology, Immunotherapy, In vivo, Inbred BALB C, Inbred C57BL, Langerhans Cells, ligand, LYMPH, LYMPH NODE, Lymph Nodes, LYMPHATIC VESSEL, Lymphatic Vessels, LYVE-1, Membrane Transport Proteins, metabolism, MHC, Mice, migration, mouse, murine, physiology, priming, Protein, Receptor, Skin, tape stripping, Team-Mueller, tolerance},

pubstate = {published},

tppubtype = {article}

}