DOCSLIB.ORG

Downloaded from Supplementary Material 4.Dcsupplemental

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

FcγRIIIa Signaling Modulates Endosomal TLR Responses in Human CD4 + T Cells Anil K. Chauhan This information is current as J Immunol published online 12 May 2017 of September 23, 2021. http://www.jimmunol.org/content/early/2017/05/12/jimmun ol.1601954 Downloaded from Supplementary http://www.jimmunol.org/content/suppl/2017/05/12/jimmunol.160195 Material 4.DCSupplemental Why The JI? Submit online. http://www.jimmunol.org/ • Rapid Reviews! 30 days* from submission to initial decision • No Triage! Every submission reviewed by practicing scientists • Fast Publication! 4 weeks from acceptance to publication *average by guest on September 23, 2021 Subscription Information about subscribing to The Journal of Immunology is online at: http://jimmunol.org/subscription Permissions Submit copyright permission requests at: http://www.aai.org/About/Publications/JI/copyright.html Email Alerts Receive free email-alerts when new articles cite this article. Sign up at: http://jimmunol.org/alerts The Journal of Immunology is published twice each month by The American Association of Immunologists, Inc., 1451 Rockville Pike, Suite 650, Rockville, MD 20852 Copyright © 2017 by The American Association of Immunologists, Inc. All rights reserved. Print ISSN: 0022-1767 Online ISSN: 1550-6606. Published May 12, 2017, doi:10.4049/jimmunol.1601954 The Journal of Immunology FcgRIIIa Signaling Modulates Endosomal TLR Responses in Human CD4+ T Cells Anil K. Chauhan Recognition of Ab-opsonized pathogens by immune cells triggers both TLR and Fc receptor signaling. Fc receptors endocytose modified nucleic acids bound to Abs and deliver them to endosomes, where they are recognized by nucleic acid–sensing TLRs (NA-TLRs). We show that in CD4+ T cells, NA-TLRs, TLR3, TLR8, and TLR9 are upregulated by FcgRIIIa-pSyk cosignaling and localize with FcgRIIIa on the cell surface. TLR9 accumulates on the cell surface, where it recognizes CpG oligonucleotide 2006. Subcellular location of NA-TLRs is a key determinant in discriminating self versus viral nucleic acid. Hydroxychloroquine used for treating systemic lupus erythematosus and a Syk inhibitor blocked NA-TLR localization with FcgRIIIa. Engaging TLR9 with CpG oligonucleotide contributes to the development of IL17A+ and IL-21+ populations. RNA-sequencing analysis showed upreg- ulation of proinflammatory cytokines, NF-kB signaling, and heat shock protein pathway RNA transcripts. These data suggest a Downloaded from role for FcgRIIIa-pSyk cosignaling in modulating NA-TLR responses in human CD4+ T cells by affecting the amounts and cellular distribution. These events are important for understanding of autoimmune pathology. The Journal of Immunology, 2017, 198: 000–000. oll-like receptors are a therapeutic target, both in auto- in the kidney biopsies of lupus nephritis patients along with IC immunity and cancer. Endosomal TLRs recognize nucleic deposits (12). The glomeruli in the kidney biopsies of proliferative http://www.jimmunol.org/ T acids and trigger innate immune responses. Nucleic acid– lupus nephritis patients show TLR9 deposits along with ICs (13). sensing TLR (NA-TLR) signaling produces type I IFNs in plas- Subcellular compartmentalization of NA-TLRs is a mechanism by macytoid dendritic cells (pDCs) and generates autoreactive B cells, which cells discriminate between modified self and viral nucleic a major driver of systemic autoimmunity (1–3). FcgRIIa receptors acids (14). TLR9, when experimentally forced to mislocalize to in innate cells endocytose DNA/RNA immune complexes (ICs) and the cell surface in HEK 293 cells, recognizes modified self-DNA, deliver them to NA-TLRs in the endosomes. Such events have not but not the viral nucleic acid (14). However, the mechanisms that been studied in CD4+ Tcells.InCD4+ T cells, TLR expression has drive NA-TLRs to the cell surface are unknown (1). Other factors been documented only at mRNA level (4, 5). Expression of TLR that regulate nucleic acid sensing are the quantity and the sig- + proteins in CD4 T cells is debated (6).TLR agonists modulate naling threshold of TLR proteins (1, 15). In SLE, necrotic cells by guest on September 23, 2021 T cell signaling during the autoimmune response (7, 8). TLR4 ac- release high mobility group box 1 (HMGB1) protein, a DNA tivation leads to the generation of IFN-g– and IL-17A–producing chaperone, which binds with DNA-ICs and is necessary to provide cells (9, 10). The nucleic acid sensing is documented in CD4+ stability to these complexes. These HMGB1-bound DNA-ICs T cells, but the receptor that facilitates nucleic acid delivery to NA- stimulate proinflammatory cytokine production via the TLR9- TLRs is unknown (8). The role of endosomal NA-TLRs in human MyD88 pathway (16). CD4+ T cell responses has not been explored. In B cells, TLR signaling coordinated with BCRs and/or Fc NA-TLR signaling contributes to autoantibody production in the receptors signaling drive cellular responses (17). Synergistic sig- mouse models of systemic lupus erythematosus (SLE), Sjo¨gren’s naling by FcgRIIa/TLR9 pathway generates a distinct signal syndrome, and arthritis (11). NA-TLR protein deposits are present compared with the BCR/TLR 9 pathway (18). Enhanced presence of NA-TLRs on the CD4+ T cell surface can establish a cross-talk, Division of Adult and Pediatric Rheumatology, Saint Louis University School of which raises the possibility of synergized signaling with the TCRs Medicine, St. Louis, MO 63104; and Department of Molecular Microbiology and and/or Fc receptors. We have earlier shown that the phosphory- Immunology, Saint Louis University School of Medicine, St. Louis, MO 63104 lation of spleen tyrosine kinase (Syk) by FcgRIIIa triggers the ORCID: 0000-0002-9487-5283 (A.K.C.). differentiation of human naive CD4+ T cells into proinflammatory Received for publication November 16, 2016. Accepted for publication April 13, IFN-g and IL-17A–producing effector T cells (19–22). FcgRIIIa- 2017. pSyk cosignaling also induces expression of NA-TLRs and type 1 This work was supported by National Institutes of Health Grant R01 A1098114 (to IFN RNA transcripts (19). The role for FcgRIIIa-pSyk as a co- A.K.C.). stimulatory signal in NA-TLR responses that contribute to the Address correspondence and reprint requests to Dr. Anil K. Chauhan, Division of + Adult and Pediatric Rheumatology, Saint Louis University School of Medicine, 1402 CD4 T cell differentiation has never been investigated. South Grand Boulevard, St. Louis, MO 63104. E-mail address: [email protected] In this study, we demonstrate that the FcgRIIIa cosignaling ac- The online version of this article contains supplemental material. cumulates functional TLR9 on the cell surface. Purified membrane Abbreviations used in this article: ATCC, American Type Culture Collection; DIC, preparations from cells activated via FcgRIIIa cosignaling show full- differential interference contrast; HCQ, hydroxychloroquine; HMGB1, high mobility length noncleaved 130 kDa TLR9 protein, whereas the cell lysates group box 1; HSP, heat shock protein; IC, immune complex; IP, immunoprecipitate; NA-TLR, nucleic acid–sensing TLR; ODN, oligodeoxynucleotide; pDC, plasmacy- show both noncleaved and cleaved forms of TLR9. TLR9 protein on toid dendritic cell; RNA-seq, RNA-sequencing; RT, room temperature; SLE, sys- the cell surface binds to CpG oligodeoxynucleotide (ODN) and en- temic lupus erythematosus; STED, stimulated emission depletion; Syk, spleen hances the differentiation of naive CD4+ T cells. NA-TLR upregu- tyrosine kinase. lation was observed in both primary human CD4+ T cells and P116 2/2 Copyright Ó 2017 by The American Association of Immunologists, Inc. 0022-1767/17/$30.00 cells, a ZAP-70 mutant of Jurkat T cells, which can signal only www.jimmunol.org/cgi/doi/10.4049/jimmunol.1601954 2FcgRIIIa-pSyk SIGNALING IN NA-TLR RESPONSES via Syk. A Syk inhibitor, P505, and hydroxychloroquine (HCQ), ment. Cells were analyzed for IL-17A and IL-21 production in flow drugs used for the treatment of SLE, inhibit the cell surface local- analysis using anti–IL-17A-PE-R700 and anti–IL-21-BV421 (BD Biosci- ization of NA-TLRs with FcgRIIIa. HMGB1 and MyD88 proteins ences). A two-tailed paired nonparametric t test was performed using Prism software to analyze the statistical difference in cytokine-producing that participate in nucleic acid sensing and TLR signaling associate populations. Conjugates were titrated and flow compensation was done with FcgRIIIa protein on the cell surface poststimulation via FcgRIIIa using PE- or allophycocyanin-conjugated isotype controls. receptor signaling. RNA-sequencing (RNA-seq) analysis shows the Cell staining for confocal imaging upregulation of IFNs, IFN-inducible genes, NF-kB signaling–driven proinflammatory cytokines, and heat shock protein (HSP) RNA Postactivation cells were harvested and washed with PBS and fixed in 4% transcripts. These results provide new insight into the role of FcgRIIIa formaldehyde for 15 min at RT. Cells were then permeabilized using cold methanol at 220˚C for 10 min. Cells were kept for 1 h in 1% BSA/PBS signaling in T cell biology. and stained using Ag-specific primary Abs at a dilution of 1:50 in BSA/ PBS for 1 h and developed using anti-species isotype-specific Alexa Fluor Materials and Methods fluorochrome conjugate (Life Technologies) at appropriate dilutions. Anti- Cells and cell lines TLR3, -TLR8, and -TLR9 Abs were purchased from R&D Systems. Anti- MyD88 and anti-HMGB1 were obtained from Cell Signaling Technologies Blood was collected with informed consent in the Saint Louis University (rabbit monoclonal). As a control for labeled ICs, we used human IgG- Rheumatology clinic. P116 cells (CRL-2676; American Type Culture conjugated with Alexa Fluor 488. Isotype controls for mouse monoclonal Collection [ATCC]), an acute T cell leukemia ZAP-70 mutant line, was and purified rabbit IgG fraction were used as negative controls (Sigma grown as per guideline from ATCC. Jurkat, HEK 293T, THP1, and Raji Chemicals). For CpG ODN 2006–Alexa Fluor 488 staining, 1:200 dilution were also obtained from ATCC. The PBMCs were isolated using Histo- of primary stock was used to give a final concentration of 0.3 mM.
Recommended publications
  • The Ligands for Human Igg and Their Effector Functions

    The Ligands for Human Igg and Their Effector Functions

    antibodies Review The Ligands for Human IgG and Their Effector Functions Steven W. de Taeye 1,2,*, Theo Rispens 1 and Gestur Vidarsson 2 1 Sanquin Research, Dept Immunopathology and Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, 1066 CX Amsterdam, The Netherlands; [email protected] 2 Sanquin Research, Dept Experimental Immunohematology and Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, 1066 CX Amsterdam, The Netherlands; [email protected] * Correspondence: [email protected] Received: 26 March 2019; Accepted: 18 April 2019; Published: 25 April 2019 Abstract: Activation of the humoral immune system is initiated when antibodies recognize an antigen and trigger effector functions through the interaction with Fc engaging molecules. The most abundant immunoglobulin isotype in serum is Immunoglobulin G (IgG), which is involved in many humoral immune responses, strongly interacting with effector molecules. The IgG subclass, allotype, and glycosylation pattern, among other factors, determine the interaction strength of the IgG-Fc domain with these Fc engaging molecules, and thereby the potential strength of their effector potential. The molecules responsible for the effector phase include the classical IgG-Fc receptors (FcγR), the neonatal Fc-receptor (FcRn), the Tripartite motif-containing protein 21 (TRIM21), the first component of the classical complement cascade (C1), and possibly, the Fc-receptor-like receptors (FcRL4/5). Here we provide an overview of the interactions of IgG with effector molecules and discuss how natural variation on the antibody and effector molecule side shapes the biological activities of antibodies. The increasing knowledge on the Fc-mediated effector functions of antibodies drives the development of better therapeutic antibodies for cancer immunotherapy or treatment of autoimmune diseases.
  • Different Types of FC Gamma-Receptors Are Involved In

    Different Types of FC Gamma-Receptors Are Involved In

    British Journal of Cancer (2000) 82(2), 441–445 © 2000 Cancer Research Campaign Article no. bjoc.1999.0940 Different types of FCγ-receptors are involved in anti- Lewis Y antibody induced effector functions in vitro M Dettke1,2 and H Loibner2 1Clinic for Blood Group Serology and Transfusion Medicine, University Hospital of Vienna, Austria; 2NOVARTIS Forschungsinstitut, Vienna, Austria Summary Stimulation of monocytes by interaction of monoclonal antibodies (mAbs) with Fc gamma receptors (FcγRs) results in the activation of various monocyte effector functions. In the present investigation we show that the anti-Lewis Y (LeY) anti-tumour mAb ABL 364 and its mouse/human IgG1 chimaera induce both antibody-dependent cellular cytotoxicity (ADCC) and the release of tumour necrosis factor α (TNF-α) during mixed culture of monocytes with LeY+ SKBR5 breast cancer cells in vitro. Although anti-LeY mAb-mediated TNF-α release paralleled ADCC activity, cytokine release required a higher concentration of sensitizing mAb than the induction of cytolysis. The determination of the FcγR classes involved in the induction of the distinct effector functions showed that anti-LeY mAb-induced cytolysis was triggered by interaction between anti-LeY mAbs and FcγRI. In contrast, mAb-induced TNF-α release mainly depended on the activation of monocyte FcγRII. Neutralization of TNF-α showed no influence on monocyte ADCC activity towards SKBR5 target cells. Our data indicate an independent regulation of anti-LeY mAb induced effector functions of ADCC and TNF-α release
  • Functional and Selective Targeting of Adenovirus to High-Affinity Fc

    Functional and Selective Targeting of Adenovirus to High-Affinity Fc

    JOURNAL OF VIROLOGY, Jan. 2001, p. 480–489 Vol. 75, No. 1 0022-538X/01/$04.00ϩ0 DOI: 10.1128/JVI.75.1.480–489.2001 Copyright © 2001, American Society for Microbiology. All Rights Reserved. Functional and Selective Targeting of Adenovirus to High-Affinity Fc␥ Receptor I-Positive Cells by Using a Bispecific Hybrid Adapter CHRISTINA EBBINGHAUS,1 AHMED AL-JAIBAJI,1 ELISABETH OPERSCHALL,2 ANGELIKA SCHO¨ FFEL,1 ISABELLE PETER,1 URS F. GREBER,3 1 AND SILVIO HEMMI * Institute of Molecular Biology1 and Institute of Zoology,3 University of Zu¨rich, CH-8057 Zu¨rich, and Institute of Medical Virology, University of Zu¨rich, CH-8028 Zu¨rich,2 Switzerland Received 1 June 2000/Accepted 29 September 2000 Adenovirus (Ad) efficiently delivers its DNA genome into a variety of cells and tissues, provided that these cells express appropriate receptors, including the coxsackie-adenovirus receptor (CAR), which binds to the terminal knob domain of the viral capsid protein fiber. To render CAR-negative cells susceptible to Ad infection, we have produced a bispecific hybrid adapter protein consisting of the amino-terminal extracellular domain of the human CAR protein (CARex) and the Fc region of the human immunoglobulin G1 protein, comprising the hinge and the CH2 and CH3 regions. CARex-Fc was purified from COS7 cell supernatants and mixed with Ad particles, thus blocking Ad infection of CAR-positive but Fc receptor-negative cells. The functionality of the CARex domain was further confirmed by successful immunization of mice with CARex-Fc followed by selection of a monoclonal anti-human CAR antibody (E1-1), which blocked Ad infection of CAR-positive cells.
  • Mouse Model Recapitulating Human Fcγ Receptor Structural and Functional Diversity

    Mouse Model Recapitulating Human Fcγ Receptor Structural and Functional Diversity

    Mouse model recapitulating human Fcγ receptor structural and functional diversity Patrick Smith1, David J. DiLillo1, Stylianos Bournazos, Fubin Li, and Jeffrey V. Ravetch2 Laboratory of Molecular Genetics and Immunology, The Rockefeller University, New York, NY 10021 Contributed by Jeffrey V. Ravetch, March 7, 2012 (sent for review March 2, 2012) The in vivo biological activities of IgG antibodies result from their a particular species, such that the absolute affinities of IgG sub- bifunctional nature, in which antigen recognition by the Fab is classes for their cognate FcγRs cannot be extrapolated between coupled to the effector and immunomodulatory diversity found in species, even for recently diverged human and primate species (1, the Fc domain. This diversity, resulting from both amino acid and 12). This situation is further complicated by the existence of poly- γ γ glycan heterogeneity, is translated into cellular responses through morphisms in the human population for Fc RIIA and Fc RIIIA γ γ that result in different affinities for huIgGs (13–16), as well as Fc receptors (Fc Rs), a structurally and functionally diverse family γ of cell surface receptors found throughout the immune system. polymorphisms in Fc RIIB regulating its level of expression or Although many of the overall features of this system are main- signaling (17). Attempts to model huIgG interactions with human FcγR-expressing cells in vitro fail to mirror the diversity of cellular tained throughout mammalian evolution, species diversity has pre- populations that may be required for an in vivo response. There- cluded direct analysis of human antibodies in animal species, and, fore, new systems to study the in vivo function of the huFcγRsystem thus, detailed investigations into the unique features of the human γ and the biological effects of engaging the activating and inhibitory IgG antibodies and their Fc Rs have been limited.
  • Fc Receptor Cross-Linking Stimulates

    Fc Receptor Cross-Linking Stimulates

    THE JOURNAL OF BIOLOGICAL CHEMISTRY VOL. 285, NO. 6, pp. 4232–4242, February 5, 2010 © 2010 by The American Society for Biochemistry and Molecular Biology, Inc. Printed in the U.S.A. Fc␥ Receptor Cross-linking Stimulates Cell Proliferation of Macrophages via the ERK Pathway* Received for publication, June 23, 2009, and in revised form, November 16, 2009 Published, JBC Papers in Press, December 8, 2009, DOI 10.1074/jbc.M109.037168 Yong Luo‡1, Jeffrey W. Pollard§¶2, and Arturo Casadevall‡ʈ3 From the Departments of ‡Microbiology and Immunology, ʈMedicine, §Developmental and Molecular Biology, and ¶Obstetrics & Gynecology and Women’s Health, Albert Einstein College of Medicine, Bronx, New York 10461 Macrophage proliferation can be stimulated by phagocytosis antibody-mediated effects. FcR, which recognizes the immuno- and by cross-linking of Fc␥ receptors (Fc␥R). In this study, we globulin Fc domain, bridges two major host defense mecha- investigated the role of Fc␥R and the signaling cascades that link nisms, innate immunity and adaptive immunity, through Fc- Fc␥R activation to cell cycle progression. This effect was medi- mediated phagocytosis (1). As the first step of Fc-mediated ated by the activating Fc␥R, including Fc␥RI and III, via their phagocytosis, antibodies opsonize microbes, which can then Downloaded from Fc␥ subunit. Further investigation revealed that the cell cycle cross-link FcR on the cell membrane. FcR cross-linking triggers machinery was activated by Fc␥R cross-linking through down- complicated signaling transduction pathways that promote stream signaling events. Specifically, we identified the extracel- phagocytosis and induces the transcription of numerous genes lular signal-regulated kinase (ERK) signaling pathway as a medi- in macrophages that contribute to subsequent inflammatory ␥ ator of signals from Fc R activation to cyclin D1 expression, and immune responses.
  • Recombinant Cynomolgus Monkey FCAR/CD89 Catalog Number: 9516-FA

    Recombinant Cynomolgus Monkey FCAR/CD89 Catalog Number: 9516-FA

    Recombinant Cynomolgus Monkey FCAR/CD89 Catalog Number: 9516-FA DESCRIPTION Source Mouse myeloma cell line, NS0-derived cynomolgus monkey FCAR/CD89 protein Gln22-Asn227, with a C-terminal 6-His tag Accession # XP005590398 N-terminal Sequence No reults obtained. Gln 22 inferred from enzymatic pyroglutamate treatment revealing Glu23 Analysis Predicted Molecular 24 kDa Mass SPECIFICATIONS SDS-PAGE 33-70 kDa, reducing conditions Activity Measured by its binding ability in a functional ELISA. When Human IgA is immobilized at 5 μg/mL, 100 μL/well, the concentration of Recombinant Cynomolgus Monkey FCAR/CD89 that produces 50% of the optimal binding response is 0.5-2.5 μg/mL. Endotoxin Level <0.10 EU per 1 μg of the protein by the LAL method. Purity >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining. Formulation Lyophilized from a 0.2 μm filtered solution in PBS. See Certificate of Analysis for details. PREPARATION AND STORAGE Reconstitution Reconstitute at 200 μg/mL in PBS. Shipping The product is shipped with polar packs. Upon receipt, store it immediately at the temperature recommended below. Stability & Storage Use a manual defrost freezer and avoid repeated freeze-thaw cycles. 12 months from date of receipt, -20 to -70 °C as supplied. 1 month, 2 to 8 °C under sterile conditions after reconstitution. 3 months, -20 to -70 °C under sterile conditions after reconstitution. DATA Bioactivity Recombinant Cynomolgus Monkey FCAR/CD89 Protein Bioactivity When Human IgA is coated at 5 µg/mL (100 μL/well), Recombinant Cynomolgus Monkey FCAR/CD89 (Catalog # 9516-FA) binds with an ED50of 0.5-2.5 μg/mL.
  • A Course on Basic Immunology

    A Course on Basic Immunology

    1 B Cells and Antibodies Abul K. Abbas UCSF FOCiS 2 Lecture outline • Functions of antibodies • B cell activation; the role of helper T cells in antibody production • Therapeutic targeting of B cells 3 The Importance of Antibodies • Humoral immunity is the defense mechanism against extracellular microbes – Most current vaccines work by stimulating effective antibody responses • Antibodies are mediators of many immune/inflammatory diseases • Antibodies are used as therapeutic agents Take home messages 4 Principles of Humoral Immunity • Antibodies are produced only by B lymphocytes. • Humoral immune responses are initiated by binding of antigen to membrane bound antibody on B cells. • Activated B cells secrete soluble antibodies of the same specificity as the membrane receptors. • Antibody responses are specialized and enhanced by signals from helper T cells. Take home messages Structure of antibody molecules 5 Diverse immunoglobulin (Ig) molecules with different specificities are generated by recombination of gene segments and variations introduced at sites of recombination. 6 B cell activation and antibody production 7 The effector functions of antibodies 88 Leukocyte Fc receptors • Activating Fc receptors on phagocytes (macrophages, neutrophils) ingest opsonized microbes for destruction: FcγRI • Fc receptor on NK cells binds to opsonized cells and kill the cells (ADCC): FcγRIII • Fc receptors with other functions: FcγRII, neonatal Fc receptor (FcRn) Take home messages 9 IgG recycling by “neonatal” FcR (FcRn) 10 Antibody production: activation of B cells Helper T cells, other stimuli Naive IgG B cell Activated B cells Activated differentiate Microbe Proliferation B cell into antibody- secreting plasma cells T-dependent and T-independent antibody responses 1111 T-independent (TI) T-cell dependent (TD) Ag Ag Ag present T cell The image cannot be displayed.
  • Mouse and Human Fcr Effector Functions

    Mouse and Human Fcr Effector Functions

    Pierre Bruhns Mouse and human FcR effector € Friederike Jonsson functions Authors’ addresses Summary: Mouse and human FcRs have been a major focus of Pierre Bruhns1,2, Friederike J€onsson1,2 attention not only of the scientific community, through the cloning 1Unite des Anticorps en Therapie et Pathologie, and characterization of novel receptors, and of the medical commu- Departement d’Immunologie, Institut Pasteur, Paris, nity, through the identification of polymorphisms and linkage to France. disease but also of the pharmaceutical community, through the iden- 2INSERM, U760, Paris, France. tification of FcRs as targets for therapy or engineering of Fc domains for the generation of enhanced therapeutic antibodies. The Correspondence to: availability of knockout mouse lines for every single mouse FcR, of Pierre Bruhns multiple or cell-specific—‘a la carte’—FcR knockouts and the Unite des Anticorps en Therapie et Pathologie increasing generation of hFcR transgenics enable powerful in vivo Departement d’Immunologie approaches for the study of mouse and human FcR biology. Institut Pasteur This review will present the landscape of the current FcR family, 25 rue du Docteur Roux their effector functions and the in vivo models at hand to study 75015 Paris, France them. These in vivo models were recently instrumental in re-defining Tel.: +33145688629 the properties and effector functions of FcRs that had been over- e-mail: [email protected] looked or discarded from previous analyses. A particular focus will be made on the (mis)concepts on the role of high-affinity Acknowledgements IgG receptors in vivo and on results from antibody engineering We thank our colleagues for advice: Ulrich Blank & Renato to enhance or abrogate antibody effector functions mediated by Monteiro (FacultedeMedecine Site X.
  • A Human CD4 Monoclonal Antibody for the Treatment of T-Cell

    A Human CD4 Monoclonal Antibody for the Treatment of T-Cell

    Research Article A Human CD4 Monoclonal Antibody for the Treatment of T-Cell Lymphoma Combines Inhibition of T-Cell Signaling by a Dual Mechanism with Potent Fc-Dependent Effector Activity David A. Rider,1 Carin E.G. Havenith,2 Ruby de Ridder,2 Janine Schuurman,2 Cedric Favre,1 Joanne C. Cooper,1 Simon Walker,1 Ole Baadsgaard,4 Susanne Marschner,5 Jan G.J. vandeWinkel,2,3 John Cambier,5 PaulW.H.I. Parren, 2 and Denis R. Alexander1 1Laboratory of Lymphocyte Signalling and Development, The Babraham Institute, Cambridge, United Kingdom; 2Genmab B.V.; 3Immunotherapy Laboratory, Department of Immunology, University Medical Center Utrecht, Utrecht, the Netherlands; 4Genmab A/S, Copenhagen K, Denmark;and 5Integrated Department of Immunology, National Jewish Medical and Research Center and University of Colorado Health Sciences Center, Denver, Colorado Abstract human antibody transgenic mice (10, 11). Zanolimumab was Zanolimumab is a human IgG1 antibody against CD4, which is assessed in clinical trials in inflammatory diseases, including in clinical development for the treatment of cutaneous and rheumatoid arthritis and psoriasis, in which it induced significant T-cell depletion in repeat dosing, and was found safe and well nodal T-cell lymphomas.Here, we report on its mechanisms of action.Zanolimumab was found to inhibit CD4 + T cells by tolerated (12). This profile led to the notion that zanolimumab combining signaling inhibition with the induction of Fc- treatment might provide benefit in T-cell malignancies, and the dependent effector mechanisms.First, T-cell receptor (TCR) mAb was entered into clinical trials for the treatment of cutaneous signal transduction is inhibited by zanolimumab through a T-cell lymphoma (CTCL;ref.
  • Fcγ Receptors As Regulators of Immune Responses

    Fcγ Receptors As Regulators of Immune Responses

    REVIEWS Fcγ receptors as regulators of immune responses Falk Nimmerjahn* and Jeffrey V. Ravetch‡ Abstract | In addition to their role in binding antigen, antibodies can regulate immune responses through interacting with Fc receptors (FcRs). In recent years, significant progress has been made in understanding the mechanisms that regulate the activity of IgG antibodies in vivo. In this Review, we discuss recent studies addressing the multifaceted roles of FcRs for IgG (FcγRs) in the immune system and how this knowledge could be translated into novel therapeutic strategies to treat human autoimmune, infectious or malignant diseases. Regulatory T cells A productive immune response results from the effec- of antigenic peptides that are presented on the surface A T cell subset that is capable tive integration of positive and negative signals that of DCs to cytotoxic T cells, T helper cells, and regulatory of suppressing the activity have an impact on both innate and adaptive immune T cells. Thus, FcγRs are involved in regulating a multitude of other antigen-specific T cells cells. When positive signals dominate, cell activation of innate and adaptive immune responses, which makes including autoreactive T cells. Depletion of regulatory and pro-inflammatory responses ensue, resulting in the them attractive targets for the development of novel T cells results in the loss of elimination of pathogenic microorganisms and viruses. immunotherapeutic approaches (FIG. 1). peripheral tolerance and the In the absence of such productive stimulation, cell activa- In this Review, we summarize our current under- development of autoimmune tion is blocked and active anti-inflammatory responses standing of the role of different members of the FcγR disease.
  • Low-Affinity Ige Receptor (CD23) Function on Mouse B Cells

    Low-Affinity Ige Receptor (CD23) Function on Mouse B Cells

    Proc. Natl. Acad. Sci. USA Vol. 86, pp. 7556-7560, October 1989 Immunology Low-affinity IgE receptor (CD23) function on mouse B cells: Role in IgE-dependent antigen focusing (antigen presentation/T-cell activation/low-affinity FcE receptor) MARILYN R. KEHRY AND LESLIE C. YAMASHITA Department of Immunology, DNAX Research Institute of Molecular and Cellular Biology, Inc., 901 California Avenue, Palo Alto, CA 94304-1104 Communicated by Ray D. Owen, July 3, 1989 (receivedfor review May 5, 1989) ABSTRACT B-cell surface immunoglobulin very effi- specifically bind to surface immunoglobulin on B lympho- ciently focuses specific protein antigens for presentation to T cytes are presented very efficiently to T cells at low concen- cells. We have demonstrated a similar role in antigen focusing trations (17-22). In contrast, antigens that do not bind to the for the low-affinity FcE receptor (FcERII) on mouse B lym- surface of antigen-presenting cells are only effectively inter- phocytes. B cells treated with an IgE monoclonal antibody to nalized, processed, and presented at very high concentra- 2,4,6-trinitrophenyl (TNP) (IgE-B cells) were 100-fold more tions (17-22). effective than were untreated B cells in presenting low concen- In the present study we propose a possible role for B- trations of TNP-antigen to T cells. Blocking the binding of IgE lymphocyte FcERII in antigen internalization. We report that to FceRII on IgE-B cells with a monoclonal antibody to FceRII low concentrations of antigen are efficiently focused into the completely eliminated this increased effectiveness. Preformed degradative pathway by means of FceRII occupied by anti- complexes of IgE anti-TNP and TNP-antigen were more ef- gen-specific IgE.
  • 1. Introduction to Immunology Professor Charles Bangham (C.Bangham@Imperial.Ac.Uk)

    1. Introduction to Immunology Professor Charles Bangham ([email protected])

    MCD Immunology Alexandra Burke-Smith 1. Introduction to Immunology Professor Charles Bangham ([email protected]) 1. Explain the importance of immunology for human health. The immune system What happens when it goes wrong? persistent or fatal infections allergy autoimmune disease transplant rejection What is it for? To identify and eliminate harmful “non-self” microorganisms and harmful substances such as toxins, by distinguishing ‘self’ from ‘non-self’ proteins or by identifying ‘danger’ signals (e.g. from inflammation) The immune system has to strike a balance between clearing the pathogen and causing accidental damage to the host (immunopathology). Basic Principles The innate immune system works rapidly (within minutes) and has broad specificity The adaptive immune system takes longer (days) and has exisite specificity Generation Times and Evolution Bacteria- minutes Viruses- hours Host- years The pathogen replicates and hence evolves millions of times faster than the host, therefore the host relies on a flexible and rapid immune response Out most polymorphic (variable) genes, such as HLA and KIR, are those that control the immune system, and these have been selected for by infectious diseases 2. Outline the basic principles of immune responses and the timescales in which they occur. IFN: Interferon (innate immunity) NK: Natural Killer cells (innate immunity) CTL: Cytotoxic T lymphocytes (acquired immunity) 1 MCD Immunology Alexandra Burke-Smith Innate Immunity Acquired immunity Depends of pre-formed cells and molecules Depends on clonal selection, i.e. growth of T/B cells, release of antibodies selected for antigen specifity Fast (starts in mins/hrs) Slow (starts in days) Limited specifity- pathogen associated, i.e.