RNA interference and receptors

@article{deFaria2023,

title = {Protocol for the analysis of double-stranded RNAs in virus-infected insect cells using anti-dsRNA antibodies},

author = {Isaque J.S. de Faria and Jean-Luc Imler and João T. Marques},

url = {https://doi.org/10.1016/j.xpro.2022.102033},

doi = {10.1016/j.xpro.2022.102033},

year  = {2023},

date = {2023-03-17},

urldate = {2023-03-17},

journal = {STAR Protocols},

volume = {4},

issue = {1},

abstract = {Characterization of double-stranded (ds)RNAs is relevant to the understanding of viral replication and immune sensing. Here, we provide a protocol describing the use of anti-dsRNA antibodies for immunofluorescence and immunoblotting in virus-infected insect cells, which can also be applied to tissues and other organisms. We describe the procedures to prepare insect cells for viral infection, followed by RNA extraction and in vitro production of synthetic dsRNA controls. We then detail the steps for dsRNA detection by immunoblotting and immunofluorescence. For complete details on the use and execution of this protocol, please refer to de Faria et al. (2022).1},

keywords = {antibody, cell bioloby, Immunology, M3i, Marques, microbiology, Microscopy, Molecular Biology},

pubstate = {published},

tppubtype = {article}

}

@article{Goto2021,

title = {Verloren negatively regulates the expression of IMD pathway dependent antimicrobial peptides in Drosophila},

author = {Pragya Prakash and Arghyashree Roychowdhury-Sinha and Akira Goto},

url = {https://www.nature.com/articles/s41598-021-94973-0},

doi = {10.1038/s41598-021-94973-0},

year  = {2021},

date = {2021-07-30},

journal = {Scientific Reports},

volume = {11},

number = {15549},

abstract = {Drosophila immune deficiency (IMD) pathway is similar to the human tumor necrosis factor receptor (TNFR) signaling pathway and is preferentially activated by Gram-negative bacterial infection. Recent studies highlighted the importance of IMD pathway regulation as it is tightly controlled by numbers of negative regulators at multiple levels. Here, we report a new negative regulator of the IMD pathway, Verloren (Velo). Silencing of Velo led to constitutive expression of the IMD pathway dependent antimicrobial peptides (AMPs), and Escherichia coli stimulation further enhanced the AMP expression. Epistatic analysis indicated that Velo knock-down mediated AMP upregulation is dependent on the canonical members of the IMD pathway. The immune fluorescent study using overexpression constructs revealed that Velo resides both in the nucleus and cytoplasm, but the majority (~ 75%) is localized in the nucleus. We also observed from in vivo analysis that Velo knock-down flies exhibit significant upregulation of the AMP expression and reduced bacterial load. Survival experiments showed that Velo knock-down flies have a short lifespan and are susceptible to the infection of pathogenic Gram-negative bacteria, P. aeruginosa. Taken together, these data suggest that Velo is an additional new negative regulator of the IMD pathway, possibly acting in both the nucleus and cytoplasm.},

keywords = {bacteria, Biochemistry, DNA, Fungi, Gene Expression, gene regulation, Genetics, hoffmann, Immunochemistry, Immunology, infection, inflammation, Innate immune cells, innate immunity, M3i, microbiology, Molecular Biology, pathogens, RNA, RNAi, Signal Transduction, Transcription},

pubstate = {published},

tppubtype = {article}

}

@article{camara_lymph_2019,

title = {Lymph Node Mesenchymal and Endothelial Stromal Cells Cooperate via the RANK-RANKL Cytokine Axis to Shape the Sinusoidal Macrophage Niche},

author = {Abdouramane Camara and Olga G Cordeiro and Farouk Alloush and Janina Sponsel and Mélanie Chypre and Lucas Onder and Kenichi Asano and Masato Tanaka and Hideo Yagita and Burkhard Ludewig and Vincent Flacher and Christopher G Mueller},

doi = {10.1016/j.immuni.2019.05.008},

issn = {1097-4180},

year  = {2019},

date = {2019-01-01},

journal = {Immunity},

volume = {50},

number = {6},

pages = {1467--1481.e6},

abstract = {Tissue-resident macrophages are receptive to specific signals concentrated in cellular niches that direct their cell differentiation and maintenance genetic programs. Here, we found that deficiency of the cytokine RANKL in lymphoid tissue organizers and marginal reticular stromal cells of lymph nodes resulted in the loss of the CD169+ sinusoidal macrophages (SMs) comprising the subcapsular and the medullary subtypes. Subcapsular SM differentiation was impaired in mice with targeted RANK deficiency in SMs. Temporally controlled RANK removal in lymphatic endothelial cells (LECs) revealed that lymphatic RANK activation during embryogenesis and shortly after birth was required for the differentiation of both SM subtypes. Moreover, RANK expression by LECs was necessary for SM restoration after inflammation-induced cell loss. Thus, cooperation between mesenchymal cells and LECs shapes a niche environment that supports SM differentiation and reconstitution after inflammation.},

keywords = {Activation, Animals, Biomarkers, Cell Differentiation, Cells, Cellular, Cellular Microenvironment, cytokine, Cytokines, deficiency, Differentiation, Endothelial Cells, ENDOTHELIAL-CELLS, environment, Expression, immune regulation, Immunology, Immunophenotyping, inflammation, LYMPH, LYMPH NODE, Lymph Nodes, lymphatic endothelial cells, Lymphoid Tissue, Macrophage, Macrophages, Mesenchymal Stem Cells, mesenchymal stromal cells, Mice, rank, RANK ligand, Receptor Activator of Nuclear Factor-kappa B, Regulation, Signal Transduction, Stromal Cells, Team-Mueller, transgenic},

pubstate = {published},

tppubtype = {article}

}

@article{sawaf_defective_2018,

title = {Defective BTLA functionality is rescued by restoring lipid metabolism in lupus CD4+ Ŧ cells},

author = {Matthieu Sawaf and Jean-Daniel Fauny and Renaud Felten and Flora Sagez and Jacques-Eric Gottenberg and Hélène Dumortier and Fanny Monneaux},

doi = {10.1172/jci.insight.99711},

issn = {2379-3708},

year  = {2018},

date = {2018-01-01},

journal = {JCI insight},

volume = {3},

number = {13},

abstract = {Coinhibitory receptors play an important role in the prevention of autoimmune diseases, such as systemic lupus erythematosus (SLE), by limiting T cell activation. B and T lymphocyte attenuator (BTLA) is an inhibitory receptor, similar to cytotoxic T lymphocyte-associated protein 4 (CTLA-4) and programmed death 1 (PD1), that negatively regulates the immune response. The role of BTLA in the pathogenesis of autoimmune diseases in humans and, more specifically, in SLE is largely unknown. We investigated BTLA expression on various T cell subsets, and we did not observe significant variations of BTLA expression between lupus patients and healthy controls. However, the enhancement of BTLA expression after activation was significantly lower in SLE patients compared with that in healthy controls. Furthermore, we found an impaired capacity of BTLA to inhibit T cell activation in SLE due to a poor BTLA recruitment to the immunological synapse following T cell stimulation. Finally, we demonstrated that defective BTLA function can be corrected by restoring intracellular trafficking and by normalizing the lipid metabolism in lupus CD4+ T cells. Collectively, our results evidence that the BTLA signaling pathway is altered in SLE T cells and highlight the potential of targeting this pathway for the development of new therapeutic strategies in lupus.},

keywords = {80 and over, Adolescent, Adult, Aged, Autoimmune Diseases, Autoimmunity, CD4-Positive T-Lymphocytes, Cell Proliferation, CTLA-4 Antigen, Dumortier, Female, France, Humans, I2CT, Imagerie, Immunologic, Immunology, Lipid Metabolism, lupus, Lupus Erythematosus, Lymphocyte Activation, Male, Middle Aged, Monneaux, Programmed Cell Death 1 Receptor, Receptors, Signal Transduction, Systemic, Team-Dumortier, Young Adult},

pubstate = {published},

tppubtype = {article}

}

@article{muller_development_2018,

title = {Development of an innervated tissue-engineered skin with human sensory neurons and Schwann cells differentiated from iPS cells},

author = {Quentin Muller and Marie-Josée Beaudet and Thiéry De Serres-Bérard and Sabrina Bellenfant and Vincent Flacher and François Berthod},

doi = {10.1016/j.actbio.2018.10.011},

issn = {1878-7568},

year  = {2018},

date = {2018-01-01},

journal = {Acta Biomaterialia},

volume = {82},

pages = {93--101},

abstract = {Cutaneous innervation is increasingly recognized as a major element of skin physiopathology through the neurogenic inflammation driven by neuropeptides that are sensed by endothelial cells and the immune system. To investigate this process in vitro, models of innervated tissue-engineered skin (TES) were developed, yet exclusively with murine sensory neurons extracted from dorsal root ganglions. In order to build a fully human model of innervated TES, we used induced pluripotent stem cells (iPSC) generated from human skin fibroblasts. Nearly 100% of the iPSC differentiated into sensory neurons were shown to express the neuronal markers BRN3A and β3-tubulin after 19 days of maturation. In addition, these cells were also positive to TRPV1 and neurofilament M, and some of them expressed Substance P, TrkA and TRPA1. When stimulated with molecules inducing neuropeptide release, iPSC-derived neurons released Substance P and CGRP, both in conventional monolayer culture and after seeding in a 3D fibroblast-populated collagen sponge model. Schwann cells, the essential partners of neurons for function and axonal migration, were also successfully differentiated from human iPSC as shown by their expression of the markers S100, GFAP, p75 and SOX10. When cultured for one additional month in the TES model, iPSC-derived neurons seeded at the bottom of the sponge formed a network of neurites spanning the whole TES up to the epidermis, but only when combined with mouse or iPSC-derived Schwann cells. This unique model of human innervated TES should be highly useful for the study of cutaneous neuroinflammation. STATEMENT OF SIGNIFICANCE: The purpose of this work was to develop in vitro an innovative fully human tissue-engineered skin enabling the investigation of the influence of cutaneous innervation on skin pathophysiology. To reach that aim, neurons were differentiated from human induced pluripotent stem cells (iPSCs) generated from normal human skin fibroblasts. This innervated tissue-engineered skin model will be the first one to show iPSC-derived neurons can be successfully used to build a 3D nerve network in vitro. Since innervation has been recently recognized to play a central role in many human skin diseases, such as psoriasis and atopic dermatitis, this construct promises to be at the forefront to model these diseases while using patient-derived cells.},

keywords = {atopic dermatitis, Axonal migration, Biological, Canada, Cells, CGRP, Chemistry, COLLAGEN, Culture, Dermatitis, development, disease, Endothelial Cells, ENDOTHELIAL-CELLS, Epidermis, Expression, Fibroblast, Fibroblasts, function, Human, Humans, Immune System, Immunology, immunopathology, IN VITRO, Induced Pluripotent Stem Cells, inflammation, INNERVATION, Maturation, migration, Models, mouse, murine, Nerve, Neurites, Neurogenic Inflammation, Neurons, NEUROPEPTIDE, Neuropeptides, physiopathology, Pluripotent Stem Cells, Psoriasis, SCHWANN CELLS, Sensory Receptor Cells, Skin, skin disease, Skin Diseases, stem, Stem Cells, SUBSTANCE, SUBSTANCE P, Team-Mueller, Tissue Engineering, TRPV1},

pubstate = {published},

tppubtype = {article}

}

@article{nehmar_therapeutic_2017,

title = {Therapeutic Modulation of Plasmacytoid Dendritic Cells in Experimental Arthritis},

author = {Ramzi Nehmar and Ghada Alsaleh and Benjamin Voisin and Vincent Flacher and Alexandre Mariotte and Victoria Saferding and Antonia Puchner and Birgit Niederreiter and Thierry Vandamme and Gernot Schabbauer and Philippe Kastner and Susan Chan and Peggy Kirstetter and Martin Holcmann and Christopher Mueller and Jean Sibilia and Seiamak Bahram and Stephan Blüml and Philippe Georgel},

doi = {10.1002/art.40225},

issn = {2326-5205},

year  = {2017},

date = {2017-01-01},

journal = {Arthritis & Rheumatology (Hoboken, N.J.)},

volume = {69},

number = {11},

pages = {2124--2135},

abstract = {OBJECTIVE: The role of plasmacytoid dendritic cells (PDCs) and type I interferons (IFNs) in rheumatoid arthritis (RA) remains a subject of controversy. This study was undertaken to explore the contribution of PDCs and type I IFNs to RA pathogenesis using various animal models of PDC depletion and to monitor the effect of localized PDC recruitment and activation on joint inflammation and bone damage. 

METHODS: Mice with K/BxN serum-induced arthritis, collagen-induced arthritis, and human tumor necrosis factor transgene insertion were studied. Symptoms were evaluated by visual scoring, quantification of paw swelling, determination of cytokine levels by enzyme-linked immunosorbent assay, and histologic analysis. Imiquimod-dependent therapeutic effects were monitored by transcriptome analysis (using quantitative reverse transcriptase-polymerase chain reaction) and flow cytometric analysis of the periarticular tissue. 

RESULTS: PDC-deficient mice showed exacerbation of inflammatory and arthritis symptoms after arthritogenic serum transfer. In contrast, enhancing PDC recruitment and activation to arthritic joints by topical application of the Toll-like receptor 7 (TLR-7) agonist imiquimod significantly ameliorated arthritis in various mouse models. Imiquimod induced an IFN signature and led to reduced infiltration of inflammatory cells. 

CONCLUSION: The therapeutic effects of imiquimod on joint inflammation and bone destruction are dependent on TLR-7 sensing by PDCs and type I IFN signaling. Our findings indicate that local recruitment and activation of PDCs represents an attractive therapeutic opportunity for RA patients.},

keywords = {Activation, Adjuvants, Aminoquinolines, Analysis, Animal, Animals, arthritis, Assay, cancer, Cells, cytokine, Cytokines, Dendritic Cells, DEPLETION, Disease Models, drug effects, Enzyme-Linked Immunosorbent Assay, Experimental, Flow Cytometry, Gene Expression Profiling, Genetics, GLYCOPROTEIN, Glycoproteins, Human, Humans, IFN, IKAROS, Ikaros Transcription Factor, imiquimod, Immunologic, Immunology, immunopathology, inflammation, interferon, Interferon Type I, interferons, Knockout, Membrane, Membrane Glycoproteins, METHOD, methods, Mice, MODULATION, mouse, Necrosis, NECROSIS-FACTOR-ALPHA, pathogenesis, Patients, Pharmacology, physiology, plasmacytoid dendritic cells, Protein, Receptor, Reverse Transcriptase Polymerase Chain Reaction, rheumatoid, rheumatoid arthritis, Serum, signaling, Team-Mueller, TLR7, Toll-Like Receptor 7, TOPICAL APPLICATION, Transcription, TRANSCRIPTION FACTOR, transcriptome, transgenic, tumor, Tumor Necrosis Factor, Tumor Necrosis Factor-alpha},

pubstate = {published},

tppubtype = {article}

}

@article{chypre_characterization_2016,

title = {Characterization and application of two RANK-specific antibodies with different biological activities},

author = {M Chypre and J Seaman and O G Cordeiro and L Willen and K A Knoop and A Buchanan and R C Sainson and I R Williams and H Yagita and P Schneider and C G Mueller},

doi = {10.1016/j.imlet.2016.01.003},

year  = {2016},

date = {2016-03-01},

journal = {Immunol.Lett.},

volume = {171},

number = {1879-0542 (Electronic)},

pages = {5--14},

abstract = {Antibodies play an important role in therapy and investigative biomedical research. The TNF-family member Receptor Activator of NF-kappaB (RANK) is known for its role in bone homeostasis and is increasingly recognized as a central player in immune regulation and epithelial cell activation. However, the study of RANK biology has been hampered by missing or insufficient characterization of high affinity tools that recognize RANK. Here, we present a careful description and comparison of two antibodies, RANK-02 obtained by phage display (Newa, 2014 [1]) and R12-31 generated by immunization (Kamijo, 2006 [2]). We found that both antibodies recognized mouse RANK with high affinity, while RANK-02 and R12-31 recognized human RANK with high and lower affinities, respectively. Using a cell apoptosis assay based on stimulation of a RANK:Fas fusion protein, and a cellular NF-kappaB signaling assay, we showed that R12-31 was agonist for both species. R12-31 interfered little or not at all with the binding of RANKL to RANK, in contrast to RANK-02 that efficiently prevented this interaction. Depending on the assay and species, RANK-02 was either a weak agonist or a partial antagonist of RANK. Both antibodies recognized human Langerhans cells, previously shown to express RANK, while dermal dendritic cells were poorly labeled. In vivo R12-31 agonist activity was demonstrated by its ability to induce the formation of intestinal villous microfold cells in mice. This characterization of two monoclonal antibodies should now allow better evaluation of their application as therapeutic reagents and investigative tools},

keywords = {Activation, Animals, ANTAGONIST, Antibodies, antibody, Antibody Affinity, Apoptosis, Assay, Cell Differentiation, Cell Surface Display Techniques, Cellular, Chemistry, comparison, Dendritic Cells, DERMAL DENDRITIC CELLS, Epithelial Cells, Epithelial microfold cell, Epitopes, Fusion, FUSION PROTEIN, HEK293 Cells, Homeostasis, Human, Humans, immune regulation, Immunization, Immunology, Immunomodulation, immunopathology, In vivo, Inbred C57BL, Intestines, Jurkat Cells, Langerhans cell, Langerhans Cells, Mice, Monoclonal, monoclonal antibody, MONOCLONAL-ANTIBODY, mouse, NF-kappa B, NF-kappaB, pathology, Protein, rank, RANK (TNFRSF11a), Receptor, Receptor Activator of Nuclear Factor-kappa B, Regulation, Secondary, Signal Transduction, signaling, Team-Mueller, therapy},

pubstate = {published},

tppubtype = {article}

}

@article{dietrich_interleukin-36_2016,

title = {Interleukin-36 potently stimulates human M2 macrophages, Langerhans cells and keratinocytes to produce pro-inflammatory cytokines},

author = {Damien Dietrich and Praxedis Martin and Vincent Flacher and Yu Sun and David Jarrossay and Nicolo Brembilla and Christopher Mueller and Heather A Arnett and Gaby Palmer and Jennifer Towne and Cem Gabay},

doi = {10.1016/j.cyto.2016.05.012},

issn = {1096-0023},

year  = {2016},

date = {2016-01-01},

journal = {Cytokine},

volume = {84},

pages = {88--98},

abstract = {Interleukin (IL)-36 cytokines belong to the IL-1 family and include three agonists, IL-36 α, β and γ and one inhibitor, IL-36 receptor antagonist (IL-36Ra). IL-36 and IL-1 (α and β) activate similar intracellular pathways via their related heterodimeric receptors, IL-36R/IL-1RAcP and IL-1R1/IL-1RAcP, respectively. However, excessive IL-36 versus IL-1 signaling induces different phenotypes in humans, which may be related to differential expression of their respective receptors. We examined the expression of IL-36R, IL-1R1 and IL-1RAcP mRNA in human peripheral blood, tonsil and skin immune cells by RT-qPCR. Monocyte-derived dendritic cells (MDDC), M0, M1 or M2-polarized macrophages, primary keratinocytes, dermal macrophages and Langerhans cells (LC) were stimulated with IL-1β or IL-36β. Cytokine production was assessed by RT-qPCR and immunoassays. The highest levels of IL-36R mRNA were found in skin-derived keratinocytes, LC, dermal macrophages and dermal CD1a(+) DC. In the blood and in tonsils, IL-36R mRNA was predominantly found in myeloid cells. By contrast, IL-1R1 mRNA was detected in almost all cell types with higher levels in tonsil and skin compared to peripheral blood immune cells. IL-36β was as potent as IL-1β in stimulating M2 macrophages, keratinocytes and LC, less potent than IL-1β in stimulating M0 macrophages and MDDC, and exerted no effects in M1 and dermal macrophages. Levels of IL-1Ra diminished the ability of M2 macrophages to respond to IL-1. Taken together, these data are consistent with the association of excessive IL-36 signaling with an inflammatory skin phenotype and identify human LC and M2 macrophages as new IL-36 target cells.},

keywords = {agonists, ANTAGONIST, BLOOD, Cells, Cellular, Chemistry, Cultured, cytokine, CYTOKINE PRODUCTION, Cytokines, Dendritic Cells, DERMATOLOGY, Expression, Human, Humans, IL-1, IL-1R1, IL-1ra, IL-36, IL-36R, Immunoassay, Immunology, immunopathology, inflammation, Interleukin, Interleukin-1 Receptor Accessory Protein, Interleukin-1 Type I, KERATINOCYTES, Langerhans Cells, Macrophage, Macrophages, messenger, Molecular Biology, Monocytes, mRNA, Myeloid Cells, pathology, Phenotype, PRODUCTION, PROINFLAMMATORY CYTOKINES, Receptor, receptor antagonist, Receptors, RNA, signaling, Skin, target, Team-Mueller, TONSIL},

pubstate = {published},

tppubtype = {article}

}

@article{cordeiro_integrin-alpha_2016,

title = {Integrin-Alpha IIb Identifies Murine Lymph Node Lymphatic Endothelial Cells Responsive to RANKL},

author = {Olga G Cordeiro and Mélanie Chypre and Nathalie Brouard and Simon Rauber and Farouk Alloush and Monica Romera-Hernandez and Cécile Bénézech and Zhi Li and Anita Eckly and Mark C Coles and Antal Rot and Hideo Yagita and Catherine Léon and Burkhard Ludewig and Tom Cupedo and François Lanza and Christopher G Mueller},

doi = {10.1371/journal.pone.0151848},

issn = {1932-6203},

year  = {2016},

date = {2016-01-01},

journal = {PloS One},

volume = {11},

number = {3},

pages = {e0151848},

abstract = {Microenvironment and activation signals likely imprint heterogeneity in the lymphatic endothelial cell (LEC) population. Particularly LECs of secondary lymphoid organs are exposed to different cell types and immune stimuli. However, our understanding of the nature of LEC activation signals and their cell source within the secondary lymphoid organ in the steady state remains incomplete. Here we show that integrin alpha 2b (ITGA2b), known to be carried by platelets, megakaryocytes and hematopoietic progenitors, is expressed by a lymph node subset of LECs, residing in medullary, cortical and subcapsular sinuses. In the subcapsular sinus, the floor but not the ceiling layer expresses the integrin, being excluded from ACKR4+ LECs but overlapping with MAdCAM-1 expression. ITGA2b expression increases in response to immunization, raising the possibility that heterogeneous ITGA2b levels reflect variation in exposure to activation signals. We show that alterations of the level of receptor activator of NF-κB ligand (RANKL), by overexpression, neutralization or deletion from stromal marginal reticular cells, affected the proportion of ITGA2b+ LECs. Lymph node LECs but not peripheral LECs express RANK. In addition, we found that lymphotoxin-β receptor signaling likewise regulated the proportion of ITGA2b+ LECs. These findings demonstrate that stromal reticular cells activate LECs via RANKL and support the action of hematopoietic cell-derived lymphotoxin.},

keywords = {Activation, Animals, Cells, Cultured, Endothelial Cells, ENDOTHELIAL-CELLS, Expression, Fibronectins, Immunization, Immunology, immunopathology, Inbred C57BL, infection, ligand, LYMPH, LYMPH NODE, Lymph Nodes, lymphoid organs, Lymphotoxin, Lymphotoxin-beta, Mice, murine, NF-kappaB, Platelet Membrane Glycoprotein IIb, PLATELETS, PROGENITORS, rank, RANK ligand, Receptor, Secondary, Signal Transduction, signaling, SINUS, Team-Mueller},

pubstate = {published},

tppubtype = {article}

}

@article{schaeffer_dermal_2015b,

title = {Dermal CD14(+) Dendritic Cell and Macrophage Infection by Dengue Virus Is Stimulated by Interleukin-4},

author = {Evelyne Schaeffer and Vincent Flacher and Vasiliki Papageorgiou and Marion Decossas and Jean-Daniel Fauny and Melanie Krämer and Christopher G Mueller},

doi = {10.1038/jid.2014.525},

issn = {1523-1747},

year  = {2015},

date = {2015-07-01},

journal = {The Journal of Investigative Dermatology},

volume = {135},

number = {7},

pages = {1743--1751},

abstract = {Dengue virus (DENV) is responsible for the most prevalent arthropod-borne viral infection in humans. Events decisive for disease development occur in the skin after virus inoculation by the mosquito. Yet, the role of human dermis-resident immune cells in dengue infection and disease remains elusive. Here we investigated how dermal dendritic cells (dDCs) and macrophages (dMs) react to DENV and impact on immunopathology. We show that both CD1c(+) and CD14(+) dDC subsets were infected, but viral load greatly increased in CD14(+) dDCs upon IL-4 stimulation, which correlated with upregulation of virus-binding lectins Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Nonintegrin (DC-SIGN/CD209) and mannose receptor (CD206). IL-4 also enhanced T-cell activation by dDCs, which was further increased upon dengue infection. dMs purified from digested dermis were initially poorly infected but actively replicated the virus and produced TNF-α upon lectin upregulation in response to IL-4. DC-SIGN(+) cells are abundant in inflammatory skin with scabies infection or Th2-type dermatitis, suggesting that skin reactions to mosquito bites heighten the risk of infection and subsequent immunopathology. Our data identify dDCs and dMs as primary arbovirus target cells in humans and suggest that dDCs initiate a potent virus-directed T-cell response, whereas dMs fuel the inflammatory cascade characteristic of dengue fever.},

keywords = {Abdominal Wall, Activation, Adhesion, adhesion molecules, Antigen-Presenting Cells, arbovirus, C-Type, Cell Adhesion, Cell Adhesion Molecules, Cell Surface, Cells, Chemistry, Confocal, Cultured, cytokine, Cytokines, cytology, Dendritic Cells, Dengue, Dengue virus, DERMAL DENDRITIC CELLS, Dermatitis, DERMIS, development, disease, Enzyme-Linked Immunosorbent Assay, Epidermal Cells, Epidermis, Human, Humans, ICAM-3, IL-4, Immunology, immunopathology, infection, Interleukin-4, Langerhans Cells, LECTIN, Lectins, Lymphocyte Activation, Macrophage, Macrophages, metabolism, Microscopy, pathogenicity, physiopathology, Receptor, Receptors, Scabies, Sensitivity and Specificity, Skin, Skin Diseases, SUBSETS, T CELL ACTIVATION, target, Team-Mueller, TNF ALPHA, Viral, viral Infection, Viral Load, virology, virus},

pubstate = {published},

tppubtype = {article}

}

@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{flacher_skin_2012,

title = {Skin langerin+ dendritic cells transport intradermally injected anti-DEC-205 antibodies but are not essential for subsequent cytotoxic CD8+ Ŧ cell responses},

author = {V Flacher and C H Tripp and B Haid and A Kissenpfennig and B Malissen and P Stoitzner and J Idoyaga and N Romani},

year  = {2012},

date = {2012-03-01},

journal = {Journal of Immunology},

volume = {188},

number = {1550-6606 (Electronic)},

pages = {2146--2155},

abstract = {Incorporation of Ags by dendritic cells (DCs) increases when Ags are targeted to endocytic receptors by mAbs. We have previously demonstrated in the mouse that mAbs against C-type lectins administered intradermally are taken up by epidermal Langerhans cells (LCs), dermal Langerin(neg) DCs, and dermal Langerin(+) DCs in situ. However, the relative contribution of these skin DC subsets to the induction of immune responses after Ag targeting has not been addressed in vivo. We show in this study that murine epidermal LCs and dermal DCs transport intradermally injected mAbs against the lectin receptor DEC-205/CD205 in vivo. Skin DCs targeted in situ with mAbs migrated through lymphatic vessels in steady state and inflammation. In the skin-draining lymph nodes, targeting mAbs were found in resident CD8alpha(+) DCs and in migrating skin DCs. More than 70% of targeted DCs expressed Langerin, including dermal Langerin(+) DCs and LCs. Numbers of targeted skin DCs in the nodes increased 2-3-fold when skin was topically inflamed by the TLR7 agonist imiquimod. Complete removal of the site where OVA-coupled anti-DEC-205 had been injected decreased endogenous cytotoxic responses against OVA peptide-loaded target cells by 40-50%. Surprisingly, selective ablation of all Langerin(+) skin DCs in Langerin-DTR knock-in mice did not affect such responses independently of the adjuvant chosen. Thus, in cutaneous immunization strategies where Ag is targeted to DCs, Langerin(+) skin DCs play a major role in transport of anti-DEC-205 mAb, although Langerin(neg) dermal DCs and CD8alpha(+) DCs are sufficient to subsequent CD8(+) T cell responses},

keywords = {administration & dosage, Animals, Antibodies, antibody, Antigen, Antigens, Biosynthesis, C-Type, C-type lectin, CD, Cell Surface, Comparative Study, Cytotoxic, Dendritic Cells, DERMATOLOGY, Gene Knock-In Techniques, Genetics, imiquimod, immune response, IMMUNE-RESPONSES, Immunization, Immunology, in situ, In vivo, Inbred BALB C, Inbred C57BL, INDUCTION, inflammation, Inflammation Mediators, Injections, Intradermal, knock-in, Langerhans Cells, LECTIN, Lectins, LYMPH, LYMPH NODE, Lymph Nodes, LYMPHATIC VESSEL, Lymphatic Vessels, mAb, Mannose-Binding Lectins, MEDIATOR, metabolism, Mice, Minor Histocompatibility Antigens, mouse, murine, Organ Culture Techniques, Ovum, pathology, physiology, Protein, Protein Transport, Rats, Receptor, Receptors, RESPONSES, Skin, SUBSETS, Surface, T-Lymphocytes, target, Team-Mueller, TLR7, transgenic},

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}

}